Any new artist name I have heard, I would look up in last.fm to gauge what they similar to and how big they are.

I used events (to show that I'm going to a live concert).

I had friends there. Another thing is people stopped using last.fm eventully.

I did artsts tagging and used shoutbox. This is where lack of community tools really kicked in. Many shoutboxes were outright dominated by undesirables.