Remember the video above? It's some of the very first Battlefield 3 gameplay footage you saw. Well, that's the closest thing you have right now to a proper look at the upcoming Battlefield 3 expansion Aftermath, which we're now learning is set in post-earthquaked (earthquaken?) Tehran.
As is standard by now, Aftermath will feature four new maps, new achievements and dog tags, and at least one new mode (the official Battlefield site says "new modes" in one spot and "new mode" in another, so it's anyone's guess right now). The maps will be urban, meaning set in various districts, streets, and villages. While there's likely to be tons of infantry combat, some vehicle combat will be featured courtesy of "heavily modified troop transports and civilian vehicles specially adapted to deliver deadly force to the enemy" -- I can only imagine what that means.
A release date for Aftermath is currently unknown, but it does come out between Armored Kill (September 2012) and End Game (winter 2013).