Ironman 3 (Extremis)

Question:

Does this supposedly take place AFTER the events in The Avengers? Or are they just sticking with the threadline of IM1 and IM2?

In the trailer when Tony says, "Nothing's been the same since New York," he's talking about what transpired in The Avengers movie, so yes... as expected, this takes place after the events in The Avengers.