Kojima has spoken in a rather detailed interview about the development story behind the recently re-announced project Metal Gear Rising: Revengence, and his ideas for the next major milestone in the stealth combat series.
"Metal Gear Solid 4 wrapped up in 2008, and the dev team took post-project time off right after that. But, of course, we were in a situation where we had to start planning for MGS5. So I started coming up with several ideas," he says, beginning this exploration behind-the-scenes of Kojima Productions.
The first ideas surrounded telling the story of The Boss and the Cobra Unit (The Pain, The Fear, The End, The Sorrow, The Fury from MGS3) during the invasion of Normandy, and he handed the project idea to the younger members of his team to develop in Summer 2008. "However, simply dropping MGS5 on the younger staff members was a bit heavy and there was resistance to doing it without my involvement," he commented.
It was at this point that Kojima was working on "a new project," which would be the continuation of Raiden's story (MGR:R) that we see today; but because of the massive weight of expectations and pressure surrounding the lucrative fifth Metal Gear Solid, it was the younger development team who felt more comfortable taking this side story, and leave the next big chapter in the hands of Kojima and the seasoned veterans in the workforce.
He confirms a new "authentic stealth MGS" is on it's way, and asks fans to be patient. We've been patient for all the previous games, so we're okay with that.