Singer unsure of Halle Berry's return
With so many characters from the original trilogy returning, fans have been shocked not to see Halle Berry's name yet. Storm survived Brett Ratner's "The Last Stand," but a return has yet to be confirmed. Singer said that an appearance from Storm is still up in the air. "I can't say. I don't know yet. And it's not necessarily a deal making aspect at all," he said. "I want to make sure it'll make sense. But I love working with her."
To me this could mean that either Storm isn't in the script, but may be written in, or she was in the script, but was written out, but may be written back in.
He says wants to make sure it'll make sense bringing Storm/Halle Berry back. Well, she was the leader of the X-Men at the end of X3, she's the mutant who has the best chance against the Sentinels, and there's little fact that she was actually in the story. If it's not completely about getting Berry to sign on (which I imagine is part of it), then story-wise, there shouldn't be much trouble including Storm in the story.