Just think about consoles based on the same Gpu's as a 580.With optimization the graphics would be 2x better than BF3.
It is based on a amd 6670. The PS3 is based on a Nvidia 7800 and it can handle better graphics than any 7800 can do if you buy the pc one. So a 6670 can go a long way but having a better GPU would be a lot better.
The PS2 is still selling so by your logic the PS3 should not have been released.