The gist is that it seems like canon, following the story of the soldiers left at Mother Base after it was attacked at the end of Ground Zeroes -- who then get sucked through a wormhole into an alternate dimension filled with zombies.
There's another Metal Gear game on the way, and it of course won't feature the talents of Hideo Kojima. No, Konami is developing a "co-op stealth game" with "familiar Metal Gear themes," set for a 2017 release on PC, PS4 and Xbox One.
This is an insult to everything Kojima built.
As insane as the stories of the previous Metal Gear games got, there was always a sophistication and grace to the series that feels completely lost now. The whole idea of this game feels lazy and exploitative of the Metal Gear name. It's 2016, why are game companies still shamelessly trying to follow in Call of Duty's footsteps?