Ok, the title might be a bit misleading. Hideo Kojima, the brain behind Metal Gear Solid saga, did in fact announce that Metal Gear Solid 4 would be the last chapter in the franchise, but then, he has made the same announcement several times in the past.
Kojima promised that he has put all his "effort and skills and experience from past 20 years" in to that final MGS chapter which, he promises, would solve all unanswered MGS questions.
Kojima then apologized for having only a video demonstration ready and promised that he would be leading a live demo of the title at a premier in Tokyo next week, July 17. There, he said, he could teach players what it's like to participate in a stealth game directly on the battlefield. "It'll look a little crazy, and I think you'll like it."
MGS 4 is scheduled for cross platform release early in 2008.
