This thread is not about what the story of AC: Brotherhood will be, but how will it be told. So far we know that Ezio tries to restore the Assassin's Guild through recruiting people, with their main headquarters to be in Rome. But in order to attain said headquarters, he must regain control of Rome through destroying towers, killing officials, and renovating districts scattered throughout the city of Rome.
What does this mean for the nature of the story in the game? In AC2, it may have been an open world game, but for the most part, the way you went about the story was linear. You would go from one mission in this location, then go to this location for the next. The mission was usually within an area, and the story of the mission was predetermined, and chronological.
How is that possible when there are so many different angles of approaching the overall task of the game? Instead of going mission by mission, you have an over arching game-long goal of taking down these towers. This gives a lot of freedom gameplay wise, but it really restricts the story, making it very vague.
Or am I misunderstanding something, and is the retaking of Rome more like a means of unlocking the next 'true' mission, which continues the main, linear story?