While at NYCC 2011 to promote next summer's epic Marvel ensemble adventure The Avengers, producer and Marvel president Kevin Feige revealed that The Avengers 2 will mix things up by introducing a new team roster, and that it will tie directly into Iron Man 3.
IGN was on the scene, where they got the following quote after asking Kevin Feige if The Avengers 2 would be introducing new superheroes into the Marvel Film universe.
"Absolutely. That's the fun of it. Introducing new characters. Seeing: 'How will things change after Iron Man goes through his next adventure? After Thor goes through his next adventure? If we do another Cap adventure, how will things change? The dynamic between them? Their own worlds? So that the dynamic in The Avengers 2 is actually quite different than it is in the first one."
"(It will lead into) what we refer to as Phase Two of this Avengers Assemble talk, which will lead to The Avengers 2. (Iron Man 3) will be a part of that"."
Other superheroes that could possible show up, who have been a part of The Avengers team in the past, include Ant-Man (who is set to get his own stand-alone film), his wife The Wasp, Quicksilver, The Scarlet Witch, her husband Vision, Black Panther (also rumored to get his own stand-alone movie), Ms. Marvel, She-Hulk, War Machine, Moon Knight, Captain Britain, Luke Cage, and Doctor Strange.