Everybody is going to have to switch to an architecture similar to cell due to the current crisis in computer architecture it's just a matter of when.
Sony already bit the bullet as far as architecture goes by moving to a system with asymetric cores. Once you go above 4 cores maintaining cache coherency tends to lead to so much bus congestion that your performance actually decreases. Every major chip designer is moving in this direction, not just IBM. Intel's Larabee is probably more similar to cell than any gpu architecture even though it gets labled as a GPGPU. And anyway, if you think programming with dma's on the SPEs is difficult, then you should try GPU programming with moving context windows and no nice floating point division. Microsoft and nintendo will have to go through the same painfull transition at some point although they do have the advantage of not being first movers here.
The division at IBM in charge of developing the 360s hardware was able to slap together a system in record time. Yes, there is RROD, however considering how quickly they did the whole thing it's astonishing (and lucky as hell) that this is the worst design flaw. It was a role of the dice and it turned out in MS's favor. Had this not happened Sony would not have been forced to release early and the cell would have been much more mature (might have had a reliable SPE compiler for instance). Many of the last second fudges might have been unnecessary and it they might have been able to pull off eliminating the GPU mostly (with a couple special purpose ICs for things like AA ala the xbox).
As a side project with two other people we already have a realtime raytracer doing 6 fps using just the 6 SPUs one one PS3 involving a number of light sources emitting sierpinski triangles (at different trippy colors) onto a number of highly reflictive sheres (so theres alot of light bouncing around) at 800x600. This is even though we haven't even begun to optimize things seriously yet, all the floating point to integer conversion for display are done on the ppu which needs to be moved over to the spus, and we are doing it through the draconian hypervisior which runs underneath linux. I honestly think that a few more usable spus clocked a little higher (not necessarily the 2007 6Ghz version shown) would have changed things drastically.
If sony sticks with the cell next generation they are set.
BTW the ps3 runs a modified version of the AIX kernel, I'm not sure but the 360 might also run AIX as they both use the POWER ISA (although what most people thing of as the OS are really userspace apps).
