Vaughn has revealed that the ending of X-Men: First Class definitely sets itself up for future sequels. Here's what he said.
"First Class is similar to Batman Begins, where you have the fun of introducing the characters and getting to know them, but that takes time. But with the second one you can just get on with it and have a rollicking good time. That's the main difference between Batman Begins and The Dark Knight. 1962 is far more grounded in the world of the '50s. I think it takes about five years for a decade to really start getting its identity, so the fun thing about this for me would be doing [a sequel] in the latter part of the decade, where you've got The Rolling Stones, The Beatles, Flower Power..."
Bryan Singer hints that the next chapter might take place in the 1970s or 1980s.
"That's an idea that's been discussed. How the characters go through time. But only to a point - they can't age too fast!"
Finally, James McAvoy, who plays Professor X in this prequel, pontificated on where he'd eventually like to take his iconic character.
"In First Class he uses Cerebro for the first time and maybe it unlocks something in his head - maybe he can't keep the voices out or something. So in the second movie his journey could be about getting himself out of a mess. And then in the third movie he become...Patrick Stewart!"