Shatner just said that other day that he has no interesting in playing James Kirk again. But I have a feeling Patrick Stewart probably would have said the same thing before Picard.
He did. Repeatedly. Because it was the way he felt. He even said "no" when they approached him with their first draft for PIC. What won him over was the SECOND draft, one they altered by including some of his suggestions about the first draft.
That being said... I wouldn't put too much weight on Shatner's "not interested" statements. If the right people with the right script come along, anything is possible.
