I am convinced that IM3, CA2, and Thor 2 will happen simultaneously, the way The Hulk, IM2, and Thor did. Natasha and Steve are looking for Bucky, Thor is off-planet, everyone is reluctant to use Bruce for less than planet-leveling threats, and let's face it, Clint is not actually that useful.

That's my theory, and I'm sticking to it until it is conclusively disproven.