Hideo Kojima's upcoming game will be console-exclusive to the PS4, Kojima Productions has announced. However, that doesn't mean that the game won't be coming to the PC, because it will be.
In a Q&A with Kojima Productions, the studio revealed that Sony's partnership with the company won't preclude them from also releasing their first title on the PC. The company states that Sony does not own a financial stake in Kojima Productions, and that the game they're making will come to the PC at some point after its PS4 release
The statement indicates that the game will, for a fact, be console-exclusive to the PS4 and thus never come out on the Xbox One or Nintendo's future platform.
The Q&A goes on to state that the new game will have nothing to do with previous franchises that Hideo Kojima was working on at Konami, so it will not be related to Metal Gear, Silent Hill, or Zone of the Enders, all of which are owned by Konami.
Sony states that it will continue to work with Konami as a publisher and that their relationship is not impacted by their decision to team up with Hideo Kojima.