Initial reaction is I don't like it... Seems very much style over substance. I'd rather see a black-and-white ascii terminal interface that was functional than all this pretty stuff without key functionality.
Can't believe auto playlists / 5-star ratings are gone. I saw the other post that said you're working on it. Great. Take down the balloons and get on that.
Where's "browse by genre"? Isn't this a basic need for a music player?
Where can I see the "Now Playing" list?
Video support is horrible. You used to have an advantage in regards to video in that your screen size of the device was bigger (not any more). The lack of video support in marketplace is unfortunate. But with this release, you had an opportunity to really have a nice win with media center integration. I was so looking forward to this! Now that I see it, I can't believe how lame it is. Media Center knows the television show, the episode, the original air date, and lots of other metadata about the show. And you've managed to incorporate a hot bowl of none of it. Nice... I have about 1/2-TB of video on media center, you expect me to go through all that one show at a time and drag-and-drop to my device? At least give me a heirarchial view of shows/episodes so I can find the show I want to sync (alphabetical by episode name is brilliant organization!).
Podcast support - jury still out. I had a workaround using Doppler and star-ratings. Star-ratings are gone, but we'll see if your native podcast support works. I actually think this might be the one improvement over the old version.
Zune Card - so far it doesn't think I've played anything, though I listened to a lot of music today, and all of it is using the AMG tags applied from the Zune 1.x software. I thought this might be cool - though would really like to see integration with last.fm or iLike.
How about updating my Windows messenger to show what I'm listening to the way WMP does?
Okay, so I'm sorry I'm so negative. Here's a positive one for you. Looking at the music on the device seems much faster.