What is the mystery “entertainment device” Google is testing?

Google is asking the Federal Communications Commission for permission to test a mysterious Wi-Fi and Bluetooth-enabled “entertainment device,” in employees homes in four U.S. cities. So inquiring minds want to know, what exactly is it? And why is Google filing for the experimental license? Does that mean the search giant is getting into manufacturing its own devices?
On the what is it category, it appears to be homebound, so it could perhaps be a set-top-box style device, or a new addendum to Google TV. Here’s what Google’s application, which was filed in December, offers in terms of information:

Google is developing an entertainment device that requires testing outside the laboratory environment. The device is in the prototyping phase and will be modified prior to final compliance testing. … Users will connect their device to home WiFi networks and use Bluetooth to connect to other home electronics equipment. This line of testing will reveal real world engineering issues and reliability of networks. The device utilizes a standard WiFi/Bluetooth module, and the planned testing is not directed at evaluating the radio frequency characteristics of the module (which are known), but rather at the throughput and stability of the home WiFi networks that will support the device, as well as the basic functionality of the device. From this testing we hope to modify the design in order to maximize product robustness and user experience. Utilizing the requested number of units will allow testing of real world network performance and its impact on applications running on the device, so that any problems can be discovered and addressed promptly. (emphasis mine)

Google asked to test 252 devices between January 17 through July 17 in Mountain View,Calif.; New York, Cambridge, Mass. and Los Angeles. Its employees will have them, so maybe you can hit a Google employee’s home to watch the Super Bowl and then start sniffing around.