Today a story came out that indicates the situation is quite the opposite.
One of the screenwriters, Roberto Orci stated:
"We're certainly hoping to include him in the shoot, because we have nothing but reverence and awe for the man."
Personally, I don't have a clue how they will work Shatner and Nimoy into the story, but I have no doubt that they will. Hopefully it will make sense and not come across as just having them there for the sake of their status in the Trek universe.
There are more comments from the writers regarding the parallel between the Cold War era when Gene Roddenberry created Star Trek and today's fear of terrorism and a few other tidbits as well over at MTV.com.