According to a Gamestop release listing, Assassin's Creed: Revelations' second DLC, the "Mediterranian Traveller" map pack", will be in stores (and presumably available online) on January 24th. The first content, a set of multiplayer characters, will be released next week.

According to Xboxgamezone, the pack is rumored to concist of six levels, including some from AC: Brotherhood:  Siena, Jerusalem, Dyers, San Donato, Firenze and the Imperial District of Constantinople.

Gamestop lists the pack for 9.99 (800 MS Points), though other sources claim it will only cost 3.99, the same price as the character set.