I think this is an interesting idea. I definitely agree with other comments here. Open it up to let users import data from Last.fm or other apps that are recording their listening trends. Then let them know what albums are being released from artists they frequently listen to.

Pulling in info then making a recommendation system would be great. Maybe work on an iTunes plugin to read star ratings and phone back to the app? Just thinking out loud here, I have no idea if something like that would be possible.