Ubisoft now has a confirmed release date for the first part of Assassin's Creed 3's alternate universe story DLC, The Tyranny of King Washington: February 19, 2013. The full title for episode one (out of three) is actually The Tyranny of King Washington: The Infamy. The DLC is confirmed for release on PlayStation 3, Xbox 360, and PC.
The episode opens with Connor Kenway awakening from an upsetting dream only to discover that the United States of America has embraced monarchy rule and crowned a king in George Washington. Connor immediately sets out to bring down the king and his rule, bringing freedom to the young nation. The press release notes that all AC3 DLC will be available for Wii U, but there's no mention of a release date yet for that platform.
Episode one will cost $9.99 / 800 MS Points a la carte, though all three episodes are also included in the Assassin's Creed 3 Season Pass ($29.99 / 2,400 MS Points).