Producer Lorenzo di Bonaventura told MTV that Bay was in fact coming back for TF4 and that the release date is the summer of 2014. Bay has another project on the go as well in between called PAIN AND GAIN (starring Dwayne Johnson and Mark Wahlberg).
Here's what di Boneventura said about Bay (for all of you outside of the US an can't watch the clip):
“Yeah Michael’s gonna direct and it’ll be releasing in the summer of 2014. We’re excited and I think the challenge there is we really are gonna do a reboot, and what that’s gonna be we don’t even know yet.”
And di Bonaventura on the story:
“Well I mean again it’s hybrid. It’s not the way—I’m not involved with Spider-Man but what I perceive Spider-Man to be is a redoing of the whole thing, [Transformers 4] is not. It’s an evolution. There’s still continuity that’s going on, and yet there’ll be a lot of new cast. Whether there’s anybody from the [original] cast, we don’t even know yet. But the truth is, it’s gonna be a whole new story. The characters that would certainly come along would be Optimus and Bumblebee I’m sure.”
And on the Jason Statham casting rumor:
“No, it’s so silly. We’ve gotta get a story first. You can’t pick characters until you have a story.”
I am definitely up for a reboot. I think the franchise needs to be overhauled while keeping some of the more popular elements of the originals. There's nothing better than a Michael Bay visual effects smorgasbord once in awhile. Are you with me?