Some long-time Metal Gear Solid fans never really gelled with the idea of Revengeance and with good reason; despite it being a spin-off, it was completely different from what we'd seen since the series began. When Platinum Games took over and the trailer was released, people lost even more faith.
And that's why this trailer should be called something like "Restoration," because it shows off some of the more awesome things Raiden will be able to do in Revengeance, including the free cutting system that many presumed had been ditched for the new version of the game. It seems almost everything in this trailer has been put in to abate the worry of fans for this game.
I'm hoping that the story trailers we've seen, featuring Solidus for the most part, are a good indication that Platinum and Kojima Productions are trying hard to make this a Metal Gear game in the truest sense - via intelligent (if occasionally shaky) plotlines.