Joakim Mogren has spoken. The bandaged and definitely fictional CEO of Moby Dick Studios, alleged developer of The Phantom Pain, spoke with GameTrailers' Geoff Keighley about the game. If by "spoke about the game" you mean "sat in front of a logo and nervously deflected questions." Which in this case we do.
While the Invisible Swede said all of Keighley's questions--is this a Metal Gear game, is it for next-gen systems, what happened to your face--will be answered at the Game Developer's Conference later this month, one detail did emerge early: The Phantom Pain is indeed running on Kojima Productions' FOX Engine.
Of course, so is the next Pro Evolution Soccer. But given the rest of the flagrant hints that The Phantom Pain is Not What It Appears, we'll take this as another notch on the Metal Gear side. Maybe Pro Evolution Soccer has always been in the Metal Gear Universe, too, who knows.
Oh, also, Mogren's bandages are nearly identical to those of the other main patient from The Phantom Pain's debut trailer. Spooky!