Free Streaming and Social Music Sites:
The chart above includes Last.fm, Imeem, MySpace Music, Playlist.com, Pandora. While not on this graph, iLike's traffic has (according to Compete.com) now surpassed Last.fm's.
Above we show Lala, 8tracks, Hype Machine, Mog and Finetune.
Twitter-centric Music Services
Included are Song.ly, Twt.fm, Blip.fm, Twisten.fm and Twiturm.
MP3 Search Engines
Portal Music Sites:
Includes AOL Music, Yahoo Music and MSN Music.