One thing that comes along with the Zune software upgrade is the ZuneCard (if this was around in the first version, I apologize, they did a damn good job of hiding it.)
It's exactly what you think it is, the Zune version of the XBOX LIve GamerCard, only with a little more. It shows your friends, what music you've listened to lately, along with what you've listenend to most. It also give you the ability to buy & send tracks, add comments, send messages, etc.
If someone hasn't created a web badge for it yet, I'm sure it's only a matter of time. If they have, drop me a link.
You can see my ZuneCard here: http://social.zune.net/member/BlogusMaximus