with his first important movie (Y tu mama tambien), I neve had thought in Cuaron, but like he did Harry P. 3, he could do an x-men movie too, but don't know if he likes the comics, or first trilogy.
I haven't vote yet, and I probably won't do it, because I don't mind the director at all, except Brett Rantner, I think he did one sequel, and wasn't the best, so sorry for him, but for X4 I preffer other director, and if Bryan never do it, then let's get other, theres so many good directors out there, Fox & co just needs to search and sign a really good one, a serious one.
I don't mind Whedon, as I've said in others thread and Josh poll, so I'd give him an opportunity. But if they don't sign him, I expect the chossen one would be better than Ratner, I mean, with a better filmography.