Rather than being an entirely new console, the device will supposedly include the same architecture as the current console but with a new drive bay and attachment area. The new box is said to also include extensive software suite for the managing of content being streamed to a TV or Hi Fi source.
In fact, doing just this may benefit them. Gearing the console to be an all-in-one device for a media center may make its steeper price tag worth it, especially if it can prove itself to be just as effective as several standalone units.
Upgrading a console, rather than designing a new one from scratch, seems like it may soon become par for the course. The more modular a console is, the more easily you can change a reference design to incorporate newer hardware. Then again, that's pretty much how the PC was started. Interestingly enough, where Sony is aiming to place the PS3 is exactly what many in the PC industry are fighting over – the living room, as a media center. Could Sony soon be competing with Intel?