A couple of weeks ago, Microsoft's Larry Hryb posted up an image of the first shipment boxes containing Xbox One consoles as they were coming off the assembly line, presumably in China. Now it looks like at least some Chinese companies are already selling replacement cases for the console several weeks before the Xbox One launches on November 22nd.
The cases were spotted on the Alibaba.com website and are being sold by a company called Gameshining, while another business called Yotosan is selling what it calls a real replacement A/C adapter for the Xbox One on the same site. It's more than likely that both companies are simply getting these parts straight off the assembly line in China and selling them to the public. It's also most likely illegal but China has a long history of pirating hardware as well.
In any case, these parts are for the Xbox One cases and power supply, not for actual full Xbox One consoles. However, it may be just a matter of time before the first Xbox One units start popping up for sale before the official launch date, along with the PlayStation 4 console from Sony. It's also possible that some people could buy these cases and then sell them as the real (fake) console on places like eBay, so be careful.