In this video taken from Pocketnowâ€™s Mango review we get to see the major changes in the Music and video hub.
The History and Whatâ€™s New section has been re-organized vertically, and SmartDJ is now fully supported. Related Artists will now also entice into signing up for a Zune Pass.
Also shown is the album art on the lock screen.
At the moment sharing music is still limited to Messaging accounts, and does not have Facebook and Twitter support, which I think is actually where sharing would be most popular.