I think they could have release it, & have 360 controller support.
Also, they should really make Half life 3 exclusive to Steam OS to drive sales.
At the moment, I do not see this as anything other than a niche machine. I bet it will be lucky to sell 20 millions in 5 years.
Lets just think for a moment: It like a console, minus the benefit of console gaming, that is standardization, & exclusives.
Its like a PC, minus to benefit of all in one machine, & will have less games to boot (as Stream games on PC are NOT compatible with Stream machine, & not all PC games are on stream to begin with).
In my opinion, they should really have just sell a unit, like apple TV, or the chrome USB stick, that allow content from Stream to be played on your TV.