Some say the future is one unified console. Others say "bwah?" Put Valve's Gabe Newell in the "bwah?" camp. His two cents:

...as long as you've got Microsoft willing to lose six or seven billion dollars to push a hardware standard, it's hard to see, you know... as long as people are willing to absorb losses on hardware. Sony's doing the same thing. I think they just announced three quarters of a billion dollars in losses. As long as you've got people willing to do that, it's hard to see why gamers aren't going to want to have subsidized hardware from those people, so I'm not sure how soon we'll get to unification.

But, even if these corporations were not willing to lose major money on hardware, would you really want a unified console? Think about it. Brian Ashcraft

Newell Interview [Eurogamer]