This video is from Halo Fest. It is said to be concept art from Halo 4, but I've never seen concept art that ******* moves, so I'm calling shenanigans. I say it's a teaser trailer. Whatever it is, it's pretty sweet. The only images that have any real context a Halo fan could recognize is the the half-of-a-UNSC-frigate Master Chief ended Halo 3 inside of, crashing into some kind of planet or space station.