A 3-D visor would not be too hard to make, they would simply have the veiw in each eye hole be slightly different, creating the illusion of depth. Have you ever used an old fashioned stereopticon (sp?) it works the same way, so that technology has been around for a long time.
As for the video, it does look fake, but it could be a hastily put together teaser, and may still be in the works. The text does remind me of the Twighlight Princess trailer "Swords will shatter; sheilds will break" (sorry if I got that wrong) But the way the twighlight princess video used it was a million times cooler.