i love last.fm its a great way to log what music you listen to, find other people that like similar things and discover more music. i have some of my own music on last.fm but havent really explored promoting it, i dont have a myspace for my music, just a simple web page. i would go the last.fm route to share my music (+ personal website) of any of those just because i like its philosophy. though i've stopped sharing new music i make because there is enough already out there and realised i had been making music for other people rather than my own ears.