Tagging

Artwork

You won’t get any artwork until you open an iTunes Store account and are logged in.
A nice marketing trick to lure people into shopping

Gracenote

iTunes uses Gracenote as its database.

The usual shit in case of classical music, Artist=Franz Schubert, Composer=Unknown.

The performer? Anybody's guess.

Same as FreeDB.

Well, not exactly, FreeDB in this case lacks the composer too but the artist is right and the description of the movements is better. At least you can see which movements belong to the same sonata

 

Well, a bit too harsh in retrospect. Ripping my sisters CD’s in iTunes on a Mac, most of the time the composer is displayed properly.

References
  1. The Complete Guide to Album Tagging, Art and Playlists in iTunes - iLounge
  2. Taming iTunes for Classical Music - Stan Brown