Metal Gear Solid 5: The Phantom Pain will release worldwide on September 1, 2015, according to an IGN video interview with Hideo Kojima that seemingly leaked ahead of time (thanks to who else but NeoGAF). Chances are the video won't be online for long, but the news is out.
Kojima said in the interview that he's "finally closing the loop" on his Metal Gear saga, meaning this is his last contribution to the series. Of course, he also recognized that he's said that after completing the last few Metal Gears. But this'll be it for Kojima.
"In that sense, this will be the final Metal Gear Solid," he said. "Even if the Metal Gear franchise continues, to me, this is the last Metal Gear."
Kojima also revealed in the interview that the game will in fact include another Metal Gear mech, based on a 1984 vision of future technology. Speaking of future technology, the game will open up at a certain point, allowing players to interact with other Mother Bases online.
Snake will also apparently be a bit less talkative in The Phantom Pain than he has been in the past, keeping relatively quiet while other characters drive the story. So... Kiefer Sutherland's time was a bit expensive, then? Just kidding. Kind of.
Either way, players will work their way through the story in a semi-episodic format, getting new story beats across multiple chapters as they piece the overarching narrative together. Sounds like it's gonna be a long wait to September.