Among the things discussed, the Steam Box might be released through multiple computer models. All of them would have the joint goal of bringing Valve games to your TV, or any other home monitors. Furthermore, the Steam Box will support Linux. However, that doesn’t mean they’ll exclude Windows from the calculation. So in other words, it will be Linux by default, but with the ability to install Windows.
That’s not all though, unlike other companies who protect their patented technology with lawsuits flying everywhere, Valve is actually open for other companies to create and release their own version of the Steam Box.
You shouldn’t expect any type of movement system through the Steam Box either, since Newell doesn’t believe it adds any new value to the system.