Just stumbled on this from SEOroundtable which talks about Panda hitting yesterday/today, next big update will be targeting low quality merchants and BBC receiving a unnatural link penalty warning recently...
http://www.youtube.com/watch?feature=player_embedded&v=TsfWqK2fQw8
http://www.youtube.com/watch?feature=player_embedded&v=TsfWqK2fQw8