The very fact that the American Revolution keeps getting confused with the Civil War I think is proof that it's a great setting, because it is yet another time period where people aren't really that familiar with all the ins and outs. There's a lot of scope to play with existing political and social structures and to create their own AC universe fictional conspiracies within those.
@Cherokeesam, I think you're spot on about the Mason stuff, it'll either be Templar or perhaps a diff group altogether, something about the 'Ones Who Came Before' even, since there are all those theories about secret Mason temples etc
Either way, I think the Masons will feature and I really hope you're right about the Cherokee. And doesn't the idea of playing a Native American Indian Assassin just feel damn right?
Edit: Just saw that free mason logo. Okay, they're probably Assassins then.
Which makes me think this game (and any extensions with the same Assassin) will mark the end of the Assassins hiding in plain sight. Since we know they all end up hiding in regional installations and camps, I think this might be the big war between Templars and Assassins that the Templars ultimately win.