While we patiently wait for Assassin’s Creed: Brotherhood’s release date, here is the forth Assassin’s Creed: Brotherhood developer diary. This dev diary talks about how the muliplayer ties into the AC story and what Desmond Miles will be doing outside of the Animus. Go ahead and watch the video before I decide to spoil it for you.
http://www.youtube.com/watch?v=qARlkJRkLoU