After Kojima was summarily removed from the credits on Metal Gear Solid 5, Silent Hills was cancelled and he was quite succinctly pushed out after his contract was up, he began work on a new game at his own Kojima Studios. Called Death Stranding, it wasn't exactly clear from the early debut trailer what it was all about, but we did see Norman Reedus with a bunch of oily hands and death fish around him...
Now though Kojima has released some more details on the game. It's going to be an open world experience, with a lot of player freedom. There's also a fixed story though with more linear elements, so it's not clear how those two opposite styles of game development will combine in the end product, but we're confident Kojima can pull it off.
Kojima also said he wanted to create new ways for players to interact and work together, rather than just trying to kill each other as soon as they stumble across one another. It's not clear what he means by that, but it's an interesting idea that has been explored in more restrictive games like Journey, before.
Death Stranding is also now in full development, with Kojima Productions having an official office for its creation and they have selected a game engine, so work can now begin in earnest.
Don't expect it to appear for at least a couple of years though.