Not long ago, all but confirmed there's probably not much Tony Stark left in him and he's not sure how much longer we'll see him in the Iron Man suit. With his contract being done after Iron Man 3, he could, if he wanted to, walk away from the franchise completely right now. But another character making big waves in the lead-up to the release of Iron Man 3 also won't be back after this summer's third Iron Man blockbuster: Pepper Potts.
Actress opened up to Empire not long ago, and confirmed that, yeah, with RDJ, so, too, goes her:
My deal is over as well. When they signed us, they signed us for three. So that's it for the moment, but you never know... I don't think they’re going to make a Pepper Potts movie, so it depends on Iron Man and Robert. I'd be open to more Pepper because I love working with Robert and it's a great franchise. Most of the time I'm a full-time mother so it's nice for me to once in a while go and work on a big hit movie with great actors and then go back to North London and resume playdates and stuff like that! I’m always happy when there’s an opportunity to do it.
If you're confused about the reference to three movies, when she has been in four Marvel films, she referring to the fact that she was never supposed to be in The Avengers at all, but was added when Robert Downey, Jr. famously pushed for her to be part of the film.
We can only assume that RDJ will be back for at least The Avengers: Age Of Ultron, but Paltrow's contract situation is a bit murkier. It will be a shame if she doesn't return, as their chemistry together is fantastic, and they are absolutely the most fun romance to watch in the Avengers universe so far (unless a certain wall-crawler shows up), as well as the most established.
It's funny that we all just assumed, "Well, of course all the Avengers and company will be back for the second Avengers movie," and took it for granted. But reports like this remind us that Hollywood can be a cruel mistress and nothing is set in stone. I guess we'll just have to cross our fingers and hope he, and by extension, she, don't feel like walking away from the franchise yet.