Rumors of a Valve console have been circulating for quite some time, and here's some more difficult to confirm information to add to the fire.
Valve's man in charge Gabe Newell has offered a few quotes in regard to the success of Steam's Big Picture Mode and bringing the PC into the living room that strongly hint that a Valve console is in the company's future. In typical Valve fashion, however, it's all very ambiguous and secretive.
A NeoGAF user has posted a link and translations from German website Golem.de where Valve employee Ben Krasnow spoke at a conference in December about a Valve console. Apparently it will be based in Linux rather than Windows in the interest of delivering an open platform for developers. Also, Newell doesn't care for Windows 8. Krasnow also said that Valve will reveal more about the hypothetical console this year.