The feature that got on of the most enthusiastic responses from the crowd the other day was album art retrieval in iTunes 7. This seems like a no brainer, I mean Apple has lots of cover art and it gives users a nice warm fuzzy to get something for free.
Scot Hacker has noticed that album art is handled a bit differently in iTunes 7. All your old album art is actually part of the music file, so you can move the music file and the art will come along for the ride. This is still supported in iTunes 7, but if you download cover art via the built in feature it isn't embedded in the file. Instead it goes to ~Music/iTunes/Album Artwork which holds a bunch of folders filled with files with a format of .itc. This, Scot presumes, allows CoverFlow to work smoothly because it just has to query that folder structure instead of looking in the actual music file. Oh, and we have heard reports from users that if you re-import all your cover art to adhere to this new format OS X's Cover art screen saver no longer works.
Scot isn't the only one at the MacDevcenter wrestling with the new cover art feature. Chris has encountered some hazards with the process. Now, the matches between your music and the iTunes Store have to be fuzzy since there isn't a codified way that all album info is stored. This results in mismatches some of the time (I was trying to get cover art for the 'Best of Queen' last night and iTunes kept assigning the cover to 'The Best of Cat Stevens.' The bottom line? Be careful when using this feature because you might not be getting the cover art you expect.