So I just recently found this really cool site called Audioscrobbler. It is a site that aggregates your music listening habits. You download a plugin for your favorite music player which sends the Artist/Album/Song to the Audioscrobbler server. This server tallys the song and adds it to your profile. Thus you are able to see what music you play and it also collects data on all the different artists so you can look at other people's playlists for music that will interest you.
I have started to send data to my account but it will take a few days before it accurately reflects what I listen to.