The video first popped up over on the Dead Space homepage. It shows a new character named John Carver struggling with life in the military while he guards the Marker. Everything goes to hell when it comes under attack.
First of all, it seems incredibly unlikely that EA would go through the trouble of hiring voice talent for a trailer for a graphic novel. However, the bigger hint at this video's true nature comes from Dead Space fans on the game's Facebook page as spotted by Joystiq. Super-sleuths have peaked through the site's source code and found code strongly suggesting this is all tied to Dead Space 3:
Finally, we've got a countdown clock leading to a reveal six days from now, with EA's E3 press conference taking place five days from now. Time to get excited, Dead Space fans. It's starting to look a lot like you've got a new game on the way.