Roberto Orci and Alex Kurtzman, writers of Transformers and this year’s Transformers: Revenge of the Fallen (and Star Trek) wrote on the Don Murphy forums and revealed that they may not be returning for Transformers 3.
“Time for fresh blood!” writes Orci. “The main reason we would move on is because we risk getting stale and comfortable. If you only sing one song for too long, you miss the opportunity to sing news songs. We’ll see.”
I am not really a fan of different writers or creative people taking over midway through a franchise. If the franchise gets repetitive or stale then different writers could be a good thing, although if it isn’t broken then no need to fix (or change) it. I guess it’s up to them as it is their careers afterall. If both Star Trek and Transformers 2 are mega hits this Summer then they will probably get offers to do other film, which may be more appealing than another robot explosion-fest.