It would be nice if you could just see "playlists from people in my circles". Right now I don't see that as an option; you need to specifically know a playlist name to search for.
I went looking for some personal listening stats yesterday, assuming they'd be there but they weren't. I can't see much about what I listen to let alone anyone else. Certainly nothing like what you get on Last.fm eg all the info on here. http://www.last.fm/user/jbond