Battery life
Battery life is an important consideration for portable devices, so I ran the iPod and Zune through a couple of tests so see how they fared. The screen brightness, volume, and backlight timers were set at the same levels on each device, and each had a fresh charge after draining the batteries completely. Audio playback was tested with a random playlist, while video cycled through an episode of Top Gear compressed in MPEG4 format.

We're comparing the Zune to an 80GB iPod here, so Apple does have the advantage. The 80GB iPod's battery is bigger than what you get on the 30GB model, and Apple claims significantly longer playback time.

With audio, the 80GB iPod manages nearly 20 hours of battery life, beating the Zune by more than six hours. Note that disabling the Zune's wireless capability gets you nearly an extra hour and a half of battery life, too—a gain of close to 13%.

The Zune's wireless capability has less of an impact on battery life with video playback, perhaps in part because the wireless component is only powered for about four hours. Predictably, the iPod is way out ahead again, but what's striking here is that it also lays waste to Apple's claimed 6.5-hour battery life for video playback. Apple only claims 3.5 hours of video playback for its 30GB iPod, but if its estimates for that device are off by the same margin, you could be looking at more than five hours of battery life.

Software and supported formats
I could go on and on about the apps associated with the iPod and Zune, but I won't—software really isn't our thing. Suffice to say that both suites work, but they do have their issues, and they're both incredibly bloated. Sadly, it appears that neither Apple nor Microsoft is willing to simply let users copy music to their portable media players without the intervention of intrusive software. It's as if they think granting users that kind of freedom will make it too easy to pirate music.

And just look how effective that's been thus far.

Amusingly, the iPod comes covered with a sticker urging users not to steal music. The Zune, however, makes no such plea; it just wants to get started. And getting started with either device is pretty easy. Installation was a snap with both the iPod and the Zune.

I should note that while Apple and Microsoft would like you to use their software to interface with the iPod and Zune, respectively, you do have options, at least on the iPod front. Recent versions of Winamp, for example, can easily transfer DRM-free audio and video to the iPod without having to mess around with—or even install—iTunes. Winamp doesn't yet work with the Zune, although it's conceivable that someone will create a plug-in if official support isn't forthcoming.

Speaking of lacking support, it's disheartening to note that the Zune isn't compatible with Microsoft's previous PlaysForSure DRM scheme. You can still get access to a subscription-based music service through what Microsoft calls the Zune Pass. This Zune Pass gives users unlimited access to most of Microsoft's online music store for $15/month, with the option to burn tracks to CD for an additional fee.

Subscription-based music services aren't for everyone, but since the Zune still supports a la carte purchases, the Zune pass simply gives users more options. You won't find any subscription services compatible with the iPod, though. Apple has never shown interest in offering music on a subscription basis, so you're left with individual downloads, or whatever MP3s you can rip from CD or otherwise obtain. The iPod at least gives you extra options when ripping your own music. Unlike the Zune, which only supports lossy audio file formats, the iPod can handle the Apple Lossless format to preserve as much of an original recording as possible.

Of course, our biggest issue with file format support on the iPod and Zune has nothing to do with lossless audio or subscription services, it's that the DRM schemes from Apple and Microsoft are incompatible with each others' players. This kind of lock-in is particularly disturbing given Apple's effective monopoly in the MP3 player market, but with both companies looking increasingly willing to offer DRM-free music in MP3 format, it may become less of an issue over time.

All the little things
When Microsoft launched the Zune, it played up the device's wireless capabilities. Unfortunately, those capabilities are limited to sharing songs between Zune devices. That's a novel feature, but since next to no one actually has a Zune, being able to wirelessly transfer songs between them is like walking around with a giant Laser Disc collection looking to swap movies. You're not going to find many takers. I have Lou Reed's This Magic Moment queued up just in case I encounter Scarlette Johannson rocking a Zune, though. But then, she'd probably have the wireless disabled to save battery life. Yeah, that's why she won't talk to me.

More disappointing than the lack of Zune-sporting celebrities with which to share songs is the fact that Microsoft hasn't extended the device's wireless capabilities to syncing or tapping songs shared over Wi-Fi networks. If you're going to bother putting a Wi-Fi chip into a portable media player, you might as well make the most of it being there. Instead, it feels like Microsoft held back, either intentionally, or because it simply didn't have the time to give the Zune more robust Wi-Fi functionality before the device's holiday launch.

The iPod can't match the Zune's wireless capabilities, but Apple does throw in a few extras, such as support for games, a stopwatch, and simple contact list, calendar, and note applications. These little touches don't make the iPod by any means, but games are particularly appropriate for the device's small screen. Indeed, Microsoft has already pledged to bring games to the Zune, and that device's button layout and larger screen should be an even better fit. However, Microsoft hasn't committed to a timeline for Zune games, saying only that they will be released before July of 2008, some 14 months from now.