The teaser trailer.
What can I say? I am a comic book movie whore.
I am very ambivalent about this film, though. As you may be aware, Bryan Singer left the X-Men franchise to direct Superman Returns, leading to a very rough development cycle for this third installment, compounded by studio refusal to push back the opening. Matthew Vaughn was brought in to direct, and worked on a script the leaked details of which are highly troubling. The good news is that it introduces Angel and the Beast in compelling ways, and it deals with Jean Grey's return as the evil Phoenix. The bad news is that [MAJOR SPOILERS] Cyclops, Magneto, and Professor X are killed by her. Seriously!
But Vaughn departed the X-Men 3 project and Rush Hour director Brett Ratner was brought in for a last-minute, well, rush job. There was some question as to whether Ratner would be forced to use the Vaughn-era script, as there seemed to be little time for substantial rewrites. By way of comparison, Superman Returns opens a month later than X-Men 3 but was essentially finishing shooting when X-Men 3 began. The trailer makes it clear that the story is in fact the same script, or a variation thereof.
Now, Brett Ratner is a competent director. He's not a visionary, he's probably not going to rock the boat, but he knows his way around the camera. He is also good friends with Bryan Singer, and it is clear from the trailer that he is keeping the visual style Singer established for the franchise. But I have serious doubts about the quality of the story that is going to be told, and the fact that Fox registered the domain name http://www.xmen3thelaststand.com combined with the spoilers above strongly suggest to me that this will be the final installment in the series. I only hope it is a good one.
All that said, the trailer itself makes the film look quite awesome.