Apple Insider questioned the validity of the model in the video noting that the reflections on the screen of the device are those usually found from a synthetic material and not from a screen using Gorilla Glass. More telling, the model number on the handset "Model NO. A1303," had already been used by Apple for the Apple iPhone 3GS and the FCC ID of "BCGA1303A" was the FCC ID for the Apple iPhone 3GS.
While the device in the video isn't the real thing, it certainly is a nice looking mock-up that gives us a good idea of what to expect in Tim Cooks hands during Apple's September 12th event.
source: GSMIsrael (translated) via AppleInsider