Pretty nice actually! I like that it's simplified, it's a bit strange how now you have so many columns and all, but it's a lot more iPod like, finally! You can now browse by artist, which is amazing (and always should have been like that).
No cover flow! Omg! Never used it much but it was the hottest iTunes thing for such a long time, and now it's gone! I don't mind.
Up next is awesome.
Gigantic font and different font sizes is a bit weird, looks very iPad ish, I think space could have been better utilised.
You can just type something and it will jump the selection to that item in your current playlist, which is awesome. Before you could only search, which would bring up maybe one result, and if you would play that, it would stop playing after it was over since that was the only item in the "search results" view. Now with type to jump and up next, that's perfect.
I like the icon.