Reel Chicago is reporting that Michael Bay's Transformers 3 will start production in Chicago on July 4th for a seven week shoot.

Chicago Film Office director Rich Moskal calls the upcoming big-budget shoot "a blockbuster in every sense of the word; in terms of economic impact, stunts and special effects."

Scheduled for a July 1, 2011 release, Transformers 3 is expected to provide the greatest amount of local union employment since Public Enemies filmed there in 2008.

While the plot is being tightly held under wraps, Michael Bay did say in a Blu-ray extra that Transformers 3 can't get any bigger, so it will have to go "sideways," in terms of overall scope and action.

He also revealed that the new Autobot being introduced will be a Ferrari 458 Italia.

Transformers 3 will shoot in six other world cities in the continuing saga of the admirable Autobots and dastardly Decepticons, who disguise themselves by transforming into everyday machinery.