Multimedia: Music, Videos, And Pictures
Music
The music interface is locked into portrait mode. You need to navigate text entries in the user interface if you want to select particular songs. Missing, however, is a way to quickly flip through albums using associated images like iOS' Cover Flow. Android has something similar, but navigating large music libraries still requires extra effort in WP7.
Microsoft's volume adjustment panel also gives you the ability to skip songs and resume playback, so you don't have to return to the Music hub for those features.
Videos
Conversely, videos are locked in landscape mode. The controls are basic and consist of rewind, play/pause, fast forward, and fill screen/fit to screen.
Pictures
The Picture tile has a news section similar to the People hub, which only lists news posts with embedded pictures. Even though this is an interesting feature, most people will probably prefer to see all tweets/posts, and not just the ones with pictures.
The Picture tile also lets you navigate to albums and sort pictures based on their parent album, date, contact who took the picture, and favorites.