Somehow, I'd expect Sony (and every game console manufacturer) would have a developers kit so they stick the source code game/engine in, and out pops compiled binary for the PS3 .. just add textures.
Hopefully after 3 years, developers which deserve the name, will be familiar with Cell programming & abandoning the Cell architecture now would peeve the developers.
It'd be a stupid move by Sony, to abandon the CELL architecture, unless they're expecting to retire all PS3 games immediately upon PS4 release, and peeve off all their customer base, like the transition from PS2 to PS3 .. but hey, it worked for M$. M$ fanboys are still thrilled about their Xbox360's.
I'll still maintain that it would be smarter to increase the SPE count, then go dual/triple/quad core, increase the clock speed, add more ram & etc - maintain backwards compatibility (for the majority of games) and yeehaw - ride the fanbase!
The CELL was the first GGPU, and the larribee the second, and the Larribee has been abandoned (in the consumer segment) by Intel. Guess it didn't work out as feasible as they expected.