It took reading the entire site to get it (bad site layout guys, you ARE trying to SELL a product, not confuse people into anger, right?) but here it is in a nutshell:
Its sole function is to keep the flatscreen a consistent distance from your face, no matter what angle you recline your chair. WOW. You could get the same effect with one of those virtual sunglasses, or just a laptop on your lap, probably for much less money. That office chair alone is pretty pricey.
Also, it is the ugliest POS I've ever seen. Uglier even than the Trashcade!