I like /mu/, rym, and especially last.fm quite a bit but I can't help but wonder - are there any other music social media websites that focus on interaction between members? Last.fm would be ideal, but the threads seem to be mostly people flexing their own tastes instead of actually interacting with other people.
In the meanwhile post your last.fm, rym, kik, whatever you use, just make sure to actually engage in conversation
last.fm/user/mastershuggie