Agent Maria Hill is going to be in Avengers 2, definitely, maybe.
Cobie Smulders, Canada's politest actress, told the Calgary Herald, that
“I hope I’m in Avengers 2. I didn’t get my invitation yet. Well, actually, they know I’m in it but they don’t know to what degree I’m in it.”
Do we really have to do this, Joss, this little dance we do every time one of these movies comes out? Can't you just send Cobie the script or at least call her on the phone and let her know not to make any plans for the spring? We want her in the movie, you want her in the movie, Tom Hiddleston probably wants her in the movie. Just do it.