SPOILER WARNING: If you haven't seen IRON MAN 3, then don't read this. Seriously.
Joss Whedon has slowly let slip little details about THE AVENGERS 2 as the train starts to leave the station on that production and speaking to IGN he talked briefly about some new and returning characters. It's been confirmed that both Scarlet Witch and Quicksilver, the brother-sister duo (and children of Magneto), are written into the film and Whedon had some comments about their involvement with the superhero team, saying:
“You know, they had a rough beginning. They’re interesting to me because they sort of represent the part of the world that wouldn’t necessarily agree with The Avengers. So they’re not there to make things easier. I’m not putting any characters in the movie that will make things easier.”
Does that mean that their mutant heritage will be addressed? I'm sure that Whedon has considered what he can and can't do in terms of violating Fox's ownership of the X-Men and I look forward to seeing his workaround for these two characters who are so closely bonded with both The Avengers and the X-Men.
In addition to that, Whedon addressed the controversial ending of IRON MAN 3 and how that factors into Tony Stark's (re)introduction into THE AVENGERS 2:
“Well, I feel like in Iron Man 3, even though he said, ‘I’ve changed' — he blew up his remote suits, but I don’t think anybody thinks he doesn’t have one anymore. The question is, if The Avengers are called, does he show up? And the answer is, ‘Yes!’”
Personally, I never felt that the ending of IRON MAN 3 stripped Tony Stark of anything, but rather reinvigorated him as someone who could continue being Iron Man without the chest baggage, as it was never really the device (however iconic) that made him the armored avenger, but the individual. Ultimately, I never got the difficulty in bringing Stark back to THE AVENGERS 2 after the events of IRON MAN 3. In fact, I think it gives Whedon more to play with, rather than just having Tony fly in, do his thing, and be done with it. Now, he has a little more conflict to work with, which makes for a much better story than a simple "let's get the gang back together" jaunt.
THE AVENGERS 2 is slated for May 1, 2015.