The latest expansion (2nd last) for BF3 has been out for almost two weeks now on the PC, and have been playing a bit here and there (mostly to clear the assignments!). There are 4 new maps introduced, mostly around the theme of earthquake affected areas in some middle-eastern country, and new character models for each class for each team are also available.
The new mode introduced called 'Scavenger' is pretty interesting actually, you start out with only a pistol, and have to go to certain points where generally random weapons will generate, and each will only have about 2 mags of ammo. (Well, not really random actually, the weapons at each point cycle through one or two weapons only). It took a while but eventually one will get the hang of the points to capture, and where the weapons will be; the key is to know where the ammo boxes are for each stage so that you can immediately max up on your available ammo. This will really give a boost to your chances of survival. Scavenger games are pretty frentic affairs, especially the one on the Epicenter map!
Conquest modes for the new maps also introduces 3 new vehicles, the Rhino (a van with a remote .50 cal turrent), Barsuk ( Vodnik with a grenade launcher ) and the Phoenix ( a modified Humvee ). As with the overall theme of this expansion, most of the terrain is pretty narrow, so it's really a double edged sword; infantry can easily sneak up on vehicles through the rubble, but then again, vehicles can set up kill zones in the narrow alleys! Plus, there's a lot of alternate routes to the objectives, so this makes for interesting ways to capture them.
Finally, a new weapon (if you can call it that) is the Crossbow, it's fires a pretty crappy bolt, but as you complete the assignments, the other 3 bolts are open for use. It's kinda interesting in that it can give other classes long range sniping ability, but then again, the LONGGGG reload time really is a killer.
Overall, Aftermath pretty much interesting in it's own right; Close Quarters had tighter maps, whereas Armored kill was a tank focused affair. Aftermath sort of fits in between these two and fills out the gaps... at least till Endgame comes along!