I believe that they have the technology to do things like that right now, but release it slowly as a marketing ploy to maximize profits.
Well, it's actually more of a "keeping manufacturing costs" down kinda thing. If a console-maker just made their system out of off-the-shelf PC parts, it would cost a fortune to manufacture the things.
Oh wait...that's exactly what Microsoft did. And they've been steadily losing an excess of $500 (or so I'm told) on each console they sell because of it.