So far you can autotag filenames from Musicbrainz, but I find the DIscogs database far more complete. I would love a discogs autotag option. Now Discogs can provide several values for things such as artist, album artist, genre and involved people. I come from Mediamonkey, and fields with more than one value are treated separating values by a semicolon, such as "Electro; Pop" for genre and "Lyrics:Richard Stillgoe; Remix: Manfred von Richstoffen" in case of "Other people involved". This info is availaible through Discogs public (I think) API.

Oh, and congratulations for this amazing software, my player of choice!