Good call, I'm going to add import from last.fm, facebook and probably iTunes.

A widget/plug-in thingy that scans your music library and adds the artists to your list would be nice.

Only if it included a caveat "only add artists with X number of tracks." God knows what kind of esoteric stuff is lurking in my music drive.

I don't own a copy of Delicious Monster, but people who do would probably fit your demographic very well. Don't know if there are enough of them to justify import functionality.