Nelson here, according to Variety Tranformers 3 gets a release date of 2011:

Paramount and DreamWorks are forging ahead with "Transformers 3," dating the movie for release on July 1, 2011.

But Michael just posted this on the forums:

I said I was taking off a year from Transformers. Paramount made a mistake in dating Transformers 3 - they asked me on the phone - I said yes to July 4 - but for 2012 - whoops! Not 2011!!! That would mean I would have to start prep in September. No way. My brain needs a break from fighting robots. -- Michael

Read and discuss at the forums.