Well, it certainly does look that way.
Check out the above clip that shows a comparison of Michael Bay's 2005 film The Island and his current release Transformers 3.
The action shots look very familiar. Sure, some of the shots are different, but if you look closely, you can see that that some of the same background cars and explosions are identical.
What do U think? Is it a cop out or just an interesting way to save money in post production??