This sounds like a really neat feature, but I would think that it wouldn't be usefull until it could rank tunes in some way that represented how much you like them. (I realize this is already in your grand-scheme-of-things) My sugestions would be playcount, and number of tunes by and artist.

Definitly put it in emplode. Emplode is after all, made by you and open source. If someone wants it without the added bulk, they could always strip it out.

Matthew