Intel are going to design a CPU?! That's crazy talk!!!
That's not the problem...
The problem is all on SCE's side... it would mean to throw away a tons of man-hours and R&D dollars spent on CELL HW and most of all on CELL optimized SW: PS3 OS, CELL compilers, the Edge/ICE programs, etc... this would be the third time in a row they do that and as consoles are becoming more and more complex multi-functional machines getting a stable SW SDK is almost more important than finalizing the HW specs.
In the end MS could afford to quite drastically change performance distribution (strong OOOe CPU and normal GPU --> weaker in-order CPU and fast GPU to make a long story very short) and not get developers too too angry at them.
SCE had the hardware down first (especially on the CPU side), but their OS was in a bloated state of flux till the last minute (tools and libraries included).
If they were to change CPU architecture to x86 they would be in danger of being late again with the SDK and the final devkit and it does not fit with the multiple times mentioned new focus on Software first (Hardware chosen in function of the Software requirements and not vice-versa).
Either Intel gives them a BIG BIG hand and they get a lot of work done... now!!!! (and they would still be losing all the development experience people got with CELL so far) or they are much better off using a CBEAv2 based CPU even if they use Larrabee as GPU... porting libGCM or whatever kind of low-level 3D API to Larrabee (written using low-level Larrabee tuned code) as well as offering a PPC version of the OpenGL driver Intel is working on for Larrabee.
Endianess and ISA of the host CPU are the least of their problems right now... besides... you want a single unified programming model for both? OpenCL to the rescue
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OpenCL + OpenGL == ultimate 3D development solution for a CELLv2 + LRB based PS4
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