Yuji Korekado, the producer of Metal Gear Rising: Revengeance, posted a photo on his Twitter of a single frame from the E3 2012 trailer of the game.
On the screen you can see Raiden holding a cyborg spine in his hand, which he presumably just ripped out of an enemy he defeated. Also notice the blue, rasterized vignetting on the screen. It could be the equivalent of the border of the screen becoming red in games like Call of Duty, when the player gets hurt. Of course, it could also be just a visual effect for the trailer.
It looks like Kojima Productions and Platinum Games are working together on the trailer. Maybe PG provides the footage and KP edits it into a trailer.
In any case, preparations for E3 are already being made. Rising is confirmed to be playable at E3, among other things Kojima Productions will show, so fans have good reason to look forward to the show.
Source: Korekado’s Twitter