Announcement Trailer has just come out. I have to admit, I'm actually a bit surprised by the choice of setting.
This is going to be a pretty tricky ground for Ubisoft to go over, methinks. There was already grumblings of discontent over making the Greek Independence Movement (in support of the Byzantines admittedly, but Greek Independence nonetheless) in the Ottoman Empire puppets of the Templars in Revelations. This is a little more contemporary and will probably feature a lot of iconic people and leaders being thrust into the 'Templar vs Assassin' conflict where people, British or American, won't want them.
Expect a lot of butt-hurt from a lot of people if Benedict Arnold ends up an Assassin while Washington turns out to be a Templar. (Hey, they hinted that Rasputin was an Assassin, so there's precedent for that kind of weirdness)