In a recent interview, Hideo Kojima announced that Metal Gear Solid 5 is being worked on. Nothing more is known about it other than it is being run on the brand new FOX engine.
He continues on in the interview saying, “There will be more infiltration, espionage, and convincing people to do you ‘a favor’, like in the last Metal Gear Solid”
He also says “Metal Gear Rising: Revengeance never pretended to be Metal Gear Solid. It’s not a game about our beloved Solid Snake. It’s a spin-off that tries something different. We haven’t seen the last of Solid Snake, despite the fact that I wanted to let him die at the end of Guns of the Patriots.” So dust off your cardboard box guys, it sounds like Solid Snake is back in action.