Emulator

That doesn't necessarily make it easier to code an emulator for it. It may mean you need a less powerful machine to emulate it in most cases.

Why not? Maybe is not rule but on this case i guess it will be easier.

I am not coder, but i guess that to take all process on the multiple Cores CPU of the PS3 will be a pain in the ass to redirect it to computer CPU which have less cores; on the 360 will be easier since his CPU is not that complex.

Technically 360 has 3 powerpc cores. There are two symmetric multithreading (SMT), finegrained hardware threads per core. So ultimately, it is like you have 6 processors. Each core contains a complement of four-way single-instruction, multiple data (SIMD) vector units called VMX128 and those cores run at 3.2 Ghz.

I don't think my 3.0 Ghz AMD Phenom (4 cores) can easily emulate those 6 processors :/.

Ok I heard one core is used for operating system purpose (does it mean only 2 cores are available for game code ?).

PS3 has only one powerpc core at 3.2 Ghz (called PPE, dual-threaded too, VMX/Altivec), has 6 SPU cores (powerful core but cannot execute a complete program as the code must be very small and the tiny memory is local to core). You may see those SPU cores working more as OpenCL cores.

As I understand PS3 games almost never use all 6 SPUs due to a game porting policies. Other than Uncharted, in most cases we see 2-3 SPUs used which should make today 4 core CPUs enough. In a year or two when 6core CPUs become more common i think that it will be enough.