It's a video of a "dirty" guy on a computer in a rusted warehouse, browsing facebook on a computer. It pulls up your info and shows him scrolling all over it, looking at pictures, etc, and then he Google Map searches your hometown. There's a shot of him driving, with cuts of him in the hollywood-style "freaking out" thing, and then he gets out of the car with either a knife or a gun, and it puts your profile pic on a piece of paper taped to the dash.
So, somewhere between reality and fear-mongering.