[Source]
The video shows an iPhone 5 compared to the 4S, and confirms everything we already know about the new iPhone, and more. According to the source this is a prototype, and was allegedly "discovered" out of production for a photoshoot and video of it booting (as well as the comparisons to the 4S) by a "friend" of someone who works at the Jincheng, Foxconn plant in China’s northern Shanxi province.
Although the device seems to be slower than a Nokia Lumia, it's also quite plain to see that the home button does in fact appear to sit a little deeper than that of the iPhone 4 variants; of course all of this will be confirmed in just under a week when Apple will announce the device, which is yet to be named.
The source added that each worker at the Jincheng factory needs to complete up to 3,000 iPhone 5 back panels every night since mass production commenced.