Quoted from another forum I frequent: -
"Download a plugin for your favourite mp3 player, and audioscrobbler keeps a record of all the songs you play EVER on its website. This is good because it lets you know how cool your taste actually is, as opposed to how cool you think it is, by generating weekly and all-time charts.
Anyway, the coolest thing is that everything is linked. Click on a song in your profile and you get a list of other people who love that tune, or listen to it a lot because they really hate it. Click on an artist and you get a list of their most popular songs. Click on a user and you see all their fave tunes, plus what they're listening to RIGHT NOW. Woo! You can also get reccommendations based on what you listen to - like amazon except that it works, and throws up things you've never heard of."
Check it out:
http://www.audioscrobbler.com
You can create groups as well and there are hundreds of them.
You can see what other people in this community listen to, whats the most listened to track etc.
I'm known as 'Socrates.'
http://www.audioscrobbler.com/user/Socrates./
You can check group stats etc.. at any time.. as well as individual stats.
Remember - AudioScrobbler is not a competition, it's more of a sharing of musical interests with others and discovering new bands/finding out who likes what etc..
Register on there before getting a plug in.. because it asks for your details when you first start WMP/Winamp with the plugin installed