I like the interface is it is more up to date. Although the style is a bit too reminiscent of MSN. Plus I find that with the extra tabs I can't make the contact list as skinny as I could before.
The integrated music and games is certainly a nice addition and free unlike MSN wanting to charge for games.
There are other improvements but I haven't really played with them yet and some things didn't seem like they were fully working yet.
All in all I think its been long overdue as the old interface reminded me more of Win98 than being on XP. Some may like that old look, but not I.