As expected, and now available on the marketplace the new additional content for Assassin's Creed: Brotherhood entitled "The Disappearance of Da Vinci" which also introduces new missions and environments, single-player, will bring with it a new map, two new modes and four characters in multiplayer. The download is queued by the web to cost 800 MP, 1.40 GB and will include all previous updates (Mt. St. Michel, Pienza, Advanced Alliance, Treasure Hunt). Here's the launch trailer that includes some new scenes.

Assassin's Creed: Brotherhood - The Disappearance of Da Vinci: Launch Trailer