Tom Cruise has signed to come back as Ethan
. no word on a director or who else may be returning.
IIRC Ghost Protocol is the best received one of the series yet; they'd be crazy not to try and get Brad Bird back, but he's said he probably won't be interested (or he might not have the time to do it either). I wonder who else they could rope in to direct.
I heard rumors that Cruise might get Chris McQuarrie to direct it in addition to writing it.
that's just a rumor so far though (even though he's mentioned). I also heard he has an Ice Station Zebra remake lined up, so he may have a scheduling conflict.
Well, whomever is chosen, I hope the choice is as inspired as Brad Bird was for Ghost Protocol.