Alright, I just had time to watch the demo. A few thoughts: It seems way too much like a "game" - like some sort of virtual reality simulation. I still find it strange how Big Boss can smoke a cigar and 24 hours would pass on the fly. Or, how Big Boss is able to fulton a Russian interpreter and five seconds later, he has joined Big Boss' outfit and is willing to help him out. Considering the time it would take him to recover, and placing him in a holding cell for interrogation - that's waaaay too fast.
I'm not sure if all of this is just gameplay, or if whether Kojima has something grand in store for the discourse. For now, I'll hope it's the latter.