found this while having a search about . seems MGS4 is not the end
source:
http://www.1up.com/do/newsStory?cId=3168338
Speaking recently, Ryan Payton revealed that Metal Gear Solid 5 could be a prequel. Payton mentioned there is still a lot of room for filling gaps as far as the boss is concerned, but MGS 4 is really the final chapter in the Solid Snake story that's all.
To quote: When Metal Gear Solid 3 was announced as a prequel to Solid Snake's adventures, many fans of the series expressed disappointment that the main narrative would not be continued or completed in that game. Now with Metal Gear Solid 4 tightly wrapping up all the loose ends of the saga, prequels may be the only way for Konami to continue fleshing out that same epic narrative.
Speaking in an interview with 1UP a week before the game's release, MGS4 assistant producer Ryan Payton said there is "still a lot of room for filling in the gaps as far as Big Boss is concerned." When asked about the possibility of a Metal Gear Solid 5, Payton responded, "There are some misunderstandings that this is the final Metal Gear game. But it's really the final chapter of the Solid Snake story. That's all."
"I'm happy we could wrap up Snake's story in MGS4," Payton stated earlier in the interview, continuing, "because it gets to the point where if we continue on with Metal Gear Solid 5 with more Solid Snake adventures, we'll get to the point where the game has absolutely no basis in reality. I do like the idea that this character has had four or five big missions and then that's when it ended, rather than have 20 missions where there's no chance in hell a secret agent could ever survive. He's had four or five really big missions, and that seems a little more realistic to me."
Any clues?
