Meanwhile, Microsoft’s Zune announced via press release that new players in different capacities and colors would be available this week, along with a software update.

Despite their different approaches, these two announcements shared a notable common thread: integrated music discovery. Each company’s new software features ways for users to find automatically generated suggestions of music they might like, the way Pandora Media Inc.’s popular personalized music lists do. Of course, music discovery also encourages users to buy more.

Apple’s new iPods include a thinner Nano with an accelerometer, which senses the direction a screen is being held in a user’s hands and flips the display horizontally or vertically. These Nanos come in eight- or 16-gigabyte versions for $149 or $199 and are available in nine bright colors. A new, thinner iPod Touch with a built-in speaker was also unveiled, and it comes in eight-, 16- or 32-gigabyte versions for $229, $299 or $399.

Microsoft’s two new Zune players come in 16- and 120-gigabyte capacities for $200 and $250, respectively. All Zunes have built-in FM tuners and wireless capability, but the new upgrade allows users to buy and download songs they hear on their Zunes’ radios via Wi-Fi, when available.

While Apple’s iPod has been a snowballing success for the company, its companion iTunes software is no slouch. To date, 65 million iTunes store accounts with associated credit cards have been set up on Macs and Windows PCs. But iTunes has always been weak on music discovery and community.

Apple (AAPL) calls iTunes 8’s ability to make smart music recommendations the “Genius” feature. The tool can automatically do two things after analyzing a selected song from your music library. First, it can generate a playlist of songs from tunes you own. Second, it can generate a list of songs you don’t own but might want to buy from the iTunes store.

MicrosoftZune’s Mixview feature displays content related to an artist with an explanation of the relationship.

Microsoft’s Zune software discovers and recommends music using categories called “Picks,” “Channels” and “Mixview.” The last of the three, Mixview, generates recommendations for other musicians and albums, as well as other Zune users with whom you might like to connect. The suggestions are based on the artist of the song you’re playing and are displayed in an interactive graphic that explains how each is linked — for instance, if your artist was influenced by a band or if a member of Zune’s social network is a top listener of the artist you’re playing.

After using the music-discovery software from Apple and Microsoft (MSFT), I felt like Apple’s Genius tool still had a lot to learn, though the company says it will improve over time as more people start using it. Zune’s software had some similar issues, but it offered recommendations in a richer, more engaging manner, encouraging me to keep digging around and learn more about my music. Though I didn’t happen to have as much time to use Zune’s software as I did Apple’s Genius, I got more out of my Zune experience.

Apple offers much more content at its iTunes store than Zune. In all categories, iTunes takes the lead: in songs, 8.5 million songs to Zune’s 4 million; in music videos, 10,000 versus 8,500; in television episodes, 30,000 versus 3,000; and in audio and video podcasts, 125,000 versus 6,000.

To analyze and learn from your music, Apple scans the contents of your music library, which may raise privacy concerns for some people. Apple says that the information it collects is completely anonymous, and that it does not and will not associate this information on its servers with you or your account.

Some of my Genius playlists were well-crafted, including songs that meshed well with one another. But outliers cropped up, such as when “Should I Stay or Should I Go” by the Clash was stuck in the middle of a list generated from Coldplay’s gentler ballad, “Green Eyes.” Some songs won’t generate playlists if you don’t have enough related songs in your library; this happened to me with the pop hit “Apologize” by Timbaland, featuring OneRepublic.

Songs from artists whose content isn’t sold in iTunes, such as The Beatles, won’t generate Genius lists, because Genius makes suggestions based only on what it sells in its iTunes catalog. Genius will soon work with songs beyond those sold in iTunes.

Genius has a bigger problem. If you hit “Play” in iTunes, a Genius sidebar appears to offer content related to a selected song. But as play continues, Genius doesn’t continuously generate new recommendations; instead, it’s stuck on the very first song that was selected — which you might have chosen two hours ago. This means music discovery must be a manual process, rather than an as-you-listen convenience.

Genius playlists can be made on a computer or iPod and sync back and forth. I synced Genius lists on two iPod touches, but this didn’t work in one test with an iPhone. Apple said it couldn’t replicate this problem and hadn’t had other reports of it.

Zune software never scans your music collection. Instead, it knows only the number of times you played a song and how you may have rated a song.

Zune’s Mixview adds a real zing to the discovery process. It is a kaleidoscope-like graphic that appears on the screen when a song, artist, album or friend’s Zune Card is selected. The selected item is surrounded by eight to 10 floating squares filled with graphics and text, each holding a related song, album, artist or graphic representation of a Zune listener who’s considered an “expert” on the selection.

Each of these related squares includes a line of text explaining its relationship to the center item. For example, as I played “(I Can’t Get No) Satisfaction” by the Rolling Stones, Cyril Davies appeared as a related artist; an image of Arthur Alexander appeared as an influencer of the Stones; a Zune community member with the tag “Rreynoso” appeared as the top listener for the band and other Stones albums were displayed.

Mixview changes as you explore it. When one of its recommendations is selected, a new Mixview is created around that selection, encouraging discovery. But Mixview has the same problem as Apple’s Genius: When one song ends and another begins, the Mixview graphic doesn’t automatically change; you must manually start Mixview for a new song. Zune says it doesn’t want to change the graphic in case a user is in mid-exploration.

Unlike Genius, Mixview shows songs and artists beyond what Zune sells online. But the company says Mixview does “favor” Zune content, and Zune Picks are limited to items sold by Zune.

Zune Picks and Channels are more passive ways of discovering music: Picks are generated for you in Zune Marketplace according to your listening habits. Zune Channels bring collections of music to Zune devices and software, but these are useful only for Zune Pass members who pay $15 monthly.

Apple’s Genius is a helpful tool when it comes to quickly making a playlist, and its iTunes sidebar might reveal fresh related content. But the Zune software truly allows people to discover more about their own music and that of others.

Edited by Walter S. Mossberg

• Email us at mossbergsolution@wsj.com. Find this and other columns and videos online free at the All Things Digital Web site: http://walt.allthingsd.com

Last year, when Microsoft Corp. introduced its Zune music player to take on Apple’s iPod juggernaut, the software giant struck out. While the Zune had a good user interface and a larger screen than the iPod, it was bigger and boxier, with clumsier controls, weaker battery life and more complex software. Its companion online music store had a much smaller catalog, a more complicated purchase process and no videos for sale. And the Zune’s most innovative feature, built-in Wi-Fi networking, was nearly useless and added little value to the players, which sold so poorly that Apple barely noticed.

The Zune Pad adds touch functionality for improved navigation.

But Microsoft is nothing if not persistent, and this week, the company is back with a second, improved round of Zunes. The chunky, older 30-gigabyte model remains in the lineup, but it’s joined by a slimmed-down full-size Zune that holds 80 gigabytes, and by a much smaller model that holds four or eight gigabytes. Prices range from $150 to $250. The 80-gigabyte Zune is available only in black, and the others come in red, green, black and pink.

We’ve been testing these new Zunes and find them to be notably better than last year’s entry. They are smaller, lighter and more attractive, and they include three big improvements. First is a new controller, called a Zune Pad, that combines buttons with a touch pad for scrolling. Second is a completely overhauled, simpler PC-software program and online store, the Zune Marketplace. Third is expanded usability of the built-in Wi-Fi, which allows you to synchronize your Zune and your PC without plugging in a cable and makes sharing songs between Zunes — its only function last year — slightly better.

Zune’s Marketplace is visually attractive.

Unfortunately for Microsoft, Apple hasn’t been standing still, either. It now has its own large-screen, wireless model, the iPod Touch, with a radical “multi-touch” interface like the iPhone’s. The screen on the Touch is larger than the one on the bigger Zunes and is much sharper. Its Wi-Fi allows you to browse the Web, watch YouTube videos and even buy music without a PC — none of which is possible on a Zune — though the Touch is $50 more and holds much less content than the new full-size Zune.

Microsoft’s new Zunes are directly aimed at the iPod Classic, Apple’s full-size, high-capacity model, and the iPod nano, its compact version. But, here again, Apple has been on the move. The 80-gigabyte Classic, which costs the same as the 80-gigabyte Zune, is slimmer than the Zune and has a flashy new interface, if a smaller screen. And the eight-gigabyte nano, which costs the same as the eight-gigabyte Zune, now plays videos and is much smaller — yet has a larger screen. Neither of these iPods includes Wi-Fi.

In addition, Apple has spiffed up its iTunes software, adding various features, including the addictive Cover Flow, which allows you to flip through all your albums with just a flick of the mouse. Cover Flow also shows up on the nano, the Classic and the Touch. Even the new Zune PC software has no interface as compelling.

And Apple still trounces Microsoft in the selection of media it sells. The iTunes store offers more than six million songs, about double what the Zune Marketplace offers, and dwarfs Microsoft’s selection of Podcasts and music videos, as well. Plus, Zune Marketplace still doesn’t sell any TV shows, movies or audiobooks, while iTunes does.

Radio Feature

Overall, we still don’t think the Zune line beats the iPods and iTunes. However, one of the Zunes, the full-size Zune 80, could give the iPod some competition, especially among new digital-player buyers who aren’t invested in the iTunes ecosystem. For the same price, it offers a significantly larger screen (albeit with the same resolution), wireless syncing and sharing, and a built-in FM radio — an existing Zune feature that the iPod lacks.

We tested the $249.99 80-gigabyte Zune 80 against Apple’s iPod Classic with the same capacity and price and then did the same for the $199.99 eight-gigabyte Zune 8 compared with the iPod nano equivalent.

We didn’t get a chance to test the battery life on the new Zune models or that of the iPod Classic and nano. But Microsoft concedes that unless you turn off Wi-Fi — one of the Zune’s key advantages — its claimed battery life is lower than Apple’s claims. Microsoft estimates as many as 19 and 24 hours of music playback with Wi-Fi on for the eight- and 80-gigabyte, respectfully. Apple claims as many as 24 hours and 30 hours, respectively, on the competitive models, which lack Wi-Fi. In the past, Apple has generally understated its battery claims, while last year, Microsoft overstated its claims.

Easier Navigating

On both Zunes, the front hosts just three buttons: the Zune Pad, a back button and a Play/Pause button. Its menus are divided into Music, Videos, Pictures, Social, Radio, Podcasts and Settings; navigating through this menu list and hundreds of songs is made easier with the Zune Pad’s touch functions. To zip through a list, we flicked a finger up or down. The top, bottom, right and left sides each work as individual buttons, as does the center of the Zune Pad.

The user interface is mainly unchanged from last year and still works very well, requiring an economical number of steps for each action.

Zune’s black, red and green colors are fine, but rather masculine — the latter reminded us of camouflage. But the pink was a glaring shade more appropriate for My Little Pony; it looks like an afterthought.

We initiated wireless syncs with the Zune software program, plugging the player into our PC the first time but leaving it disconnected each time after that. Wireless syncing took a little longer than with a cord and must be initiated by the user from within the player’s settings. One frustration: Presumably to save battery life, the Zune disconnects from the network periodically and then must reconnect the next time you want to use the Wi-Fi. Also, the Zune can’t wirelessly sync if you’re at a public hot spot that requires you to log in or pay.

Intelligent Syncing

This year’s Zunes also introduce a concept Microsoft intends to build on: intelligent, or automated, syncing. If you have your Zune set to sync only some of your music, not all, and drag an artist’s name onto the Zune icon in the PC software, the software will thereafter automatically sync every song you add to the PC from that artist. Microsoft believes many people would welcome such automation.

The Zune’s FM radio is well-designed and easy to use. Using the Zune Pad to flick left or right along the station grid, our Zunes detected numerous static-free stations, and we marked certain stations as presets by holding down the center button. Each radio’s digital data appeared on-screen, including the artist and song title.

We shared songs between our Zunes, beaming tracks from the 80-gigabyte to the eight-gigabyte and vice versa. A wirelessly shared song can be played by the recipient three times whenever they choose. Microsoft has removed the three-day time limit that applied last year. A minute of playing time, or half the duration of a song (whatever comes first) constitutes one play. At first, it took our Zunes a couple tries to recognize one another, even though they were both set to share music. And we noted that invitations to accept shared music don’t include any information about the music, so you could get stuck downloading an annoying tune or one you already own.

Photo Finish

Photos and videos looked great on the Zunes — about as good as they do on the comparable iPod nanos and better than on the iPod Classic because that iPod model’s screen is much smaller than its Zune counterpart’s. However, album art, which is often lower-resolution than normal photos, looked grainier on the big Zune than on the big iPod. And none of the Zunes came close to the stunning photo and video quality offered on the iPod Touch and the iPhone.

We didn’t get to test Zune’s a la carte point system for buying and downloading tracks because it wasn’t up and running yet. Neither were music-video downloads. We each had Zune Pass accounts, which work like subscriptions. If the Zune account stops, all content acquired during the user’s subscription is lost.

Album Focus

Navigating through Zune’s software can be a tad confusing. Four categories at the top left of your PC’s screen are meant to help: Collection, Device, Marketplace and Social. Collection shows your downloaded or owned content and focuses a bit too much on albums, which are becoming less significant with the ever-growing popularity of digital music. One example of this is the Collection’s default center panel shows album art sorted by date added.

Zune Marketplace’s artist pages really shine. Upon selecting a band or artist, a rich, full-screen background image of that group or person appears on the page with lists of songs floating atop the image. Various still photos of each artist are included; we found 10 for Mary Chapin Carpenter and 15 for Nelly Furtado.

A full-screen artist page for Avril Lavigne on Zune Marketplace

After listening to a Yo-Yo Ma album in her music collection, Katie wanted to download additional performances of the famous cellist from the Zune Marketplace online store. But, unlike iTunes, Zune’s software program doesn’t offer a way to link directly from your Collection to Marketplace for buying more of a certain artist or another song from an album you already own.

Another navigational hiccup in Zune’s Marketplace is its inability to bookmark searches. If, after searching in Zune’s online store to buy and download more Yo-Yo Ma, Katie looked in her Collection to see which piece she played last or liked most, then returned to the online store, her Marketplace store search would be lost and she’d need to start over. The iTunes store bookmarks your place during searches, allowing you to navigate through any other part of iTunes before returning to the idle search.

Zune tries to compensate for this glitch by identifying songs in the online store that you already own — either bought through Zune Marketplace or from other sources — with an “In Collection” label so you don’t accidentally buy content you already own. Likewise, if a song in your Collection is already synched to be on the player, a tiny Zune icon appears beside that song title.

Unlike iTunes, Zune software can’t create smart playlists. And it only offers two views, Browse and List, versus three in iTunes: Cover Flow, lists, and lists with album art.

Microsoft has greatly improved the Zune hardware and software this time. But it seems to be competing with Apple’s last efforts, not its newest ones.

• Email mossbergsolution@wsj.com