Review: HTC Titan II for AT&T
Microsoft's Zune software is the Hub for music, video, and other media-type content on all Windows Phones. It's not only the media player app, but has the Windows Marketplace for Mobile tossed in, too.
The user interface for playing back media is fine, and does all that I want it to. I like that Microsoft automatically pulls down artist info from the Zune store. Syncing with your existing music library, whether it be on a Mac or a Windows machine, is easy to do with free software.
The newest version of Windows Phone supports a feature called connected apps. What it does is recognize applications that are all related. In the Zune Hub, for example, this means that if you've downloaded Slacker, Vevo, and Rhapsody on your own, you'll see all of them in the Zune Hub.
Music sounded excellent when sent to my favorite headphones, and video looked great on the screen. I do wish the T2 (and Windows Phones in general) was more compatible with content purchased from Apple's iTunes music/video store.