If we consider the fact that having two to three forms of a console available at once is a phenomenon exclusive to this generation of gaming then this bit of speculation from Microsoft CEO Steve Ballmer is quite a change in what producing and owning a console means. In speaking at a recent UW speech Ballmer casually dropped that they possibly, maybe could at some point be introducing new forms of the 360 at varying price points.
He's talking about ways to interact with Microsoft on your television, and the two different approaches they take to this (one being an open to any computer way and the other being they mores structured 360 way). What is kind of, maybe, sort of hinted at is that we might see 360s (or something based off the 360) that are simply for streaming movies and TV or simply for gaming or simply for something else. The idea here is, if I'm reading his off-the-cuff quote correctly, that the 360 can be the platform for Microsoft's tools for interacting with your television.