Last.fm

Social Software for Audio/music listening

http://www.last.fm/

http://www.last.fm/user/BillSeitz - eventually stopped (2019-09-11) Music Discovery And Mobile

Jun'2007: bought by CBS.

Has ITunes "auto-scrobbler" plug-in to record what you listen to.

• but doesn't seem to import existing ratings from ITunes

Doesn't seem to have good way to find your friends who already have LastFm accounts. Or maybe nobody in my GMail address book is a member...