If they decided to make an X-men 4 movie would Ian Mckellen return as Magneto?

Question

because at the end of X-men the Last Stand he moved the chess piece without touching it after being cured wich means that his powers are coming back and the cure is temporary.

Answer 1

Looks like they did that to leave an opening for #4. I'd hate to see them use another actor for Magneto, but hey, Hollywood's made that mistake before.

Answer 2

Why not? He does a good job at the role. I think Mystique is going to be plenty pissed at him, though.

Answer 3

of course, they can't stop after using him 3 times