Once you get used to the fact that people drive on the right in the US, (they felt the need to stick it to the Brits every step of the way, didn't they?) the thing that surprises you the most is who gets the right of way.
Pedestrians. Yes, that's right.
OK, so you shouldn't jaywalk and cross the road wherever you freakin' want to. As long as you don't do that, you're king of the road!
I think this has happened so many times so far - I come to an intersection, and stare into the distance waiting for the vehicles on the road to go past. Suddenly I realise that the car's stopped and the person driving is waving at me to go ahead and cross. And every time, I find myself thanking them all surprised and hurriedly, feeling bad about not having crossed sooner.
Had I expected the same back home and acted on it, I would've been roadkill long, long ago.