Little is known about the next chapter in the Metal Gear series. We do know that the main character is Raiden and that the gameplay will be enhance considerably with the hack and slash style. How this blends in with the stealth genre created by MGS won’t be known until the game releases, which could be as late as holiday 2012.
The Metal Gear Solid Rising storyline isn’t quite clear, although it most likely takes place between the events of MGS2 and MGS4. A lot happened between these two games, and only a few tidbits were referenced in MGS4. The main storyline seems to be Raiden’s rescue attempt of Sunny, the infant daughter of Olga, and his subsequent capture by the Patriots. Throw in Eva, Vamp, and Solidus, along with the fallout from the events of MGS2, and what you have is one thrilling and action packed game. Its probably safe to say that the various overtones that were present in MGS2 and MGS4 will not be present in MGS Rising.
So how should Rising play out? The opening scene should focus on a heavily fortified retreat where Solidus is kept, probably guarded by Vamp. Vamp is on a phone getting word that the compound was discovered and is about to be assaulted by several hunting gears, manned and unmanned, that are under the direction of the Patriots. Unknown to Vamp, trailing behind this group is Raiden, who is tracking Patriot operatives in hopes of finding the location of where Sunny is kept. As the hunting gears arrive at the retreat, a battle ensues. Raiden helps Vamp to repel the assault and escape with Solidus. Afterward Raiden and Vamp fight, because they hate each other, but come to an agreement regarding the location of Sunny. Vamp knows the location and gives it to Raiden. He heads off to rescue Sunny, and the rest of the Metal Gear Solid Rising storyline is up to Kojima Productions.
Reference:
http://www.examiner.com/video-game-news-in-national/kojima-productions-further-comment-on-metal-gear-solid-rising-s-development