The tentative DLC for Assassin’s Creed 3 will have a crazy optional story which the AC3 director, Alex Hutchinson, described as a “what the f*** chunk of story that, if you missed it, the next games will still make sense”. The developers made note of their indecisiveness on whether to keep the side story or not, saying that there are lines to be drawn. They also admitted that they have not started work on the DLC, and will not, until the Assassin’s Creed 3 core game is finished.
Source: [EuroGamer]