According to the UGOGamesBlog, Marvel Ultimate Alliance 2 will not ship this year as planned.
The news came from Comic Con last week. From the site:
I also asked the Activision rep if they still planned on releasing Marvel Ultimate Alliance this fall, the same time that they plan on releasing Spiderman. I was surprised to hear that, “No, MUA 2 will not be out in 2008” despite other reports. Activision is “sticking” with Spiderman for the holiday season for its superhero game. Probably smart ideas as you don’t want to split your own market share.