I dunno, 6/29/12 is a good way off. I am hoping that maybe those who planed the first release date learned their lesson by not being overly ambitious with time estimation versus actual work done (hiring actors, filming time, CGI animation, special effects, music score, etc)--kinda how those around Ghostbusters 3 are behaving about 2011.
Another reason I believe Star Trek didn't release in Christmas 2008, is because of the other movies at that time, and along with consideration of target audiences with crowd numbers during different times of the year. It turns out that summer was a better idea, for sure.
"Why is any object we don't understand always called 'a thing' ?" ~ Dr. Leonard H. McCoy, Star Trek: The Motion Picture