I have no reason to believe that AMD systems will get better performance simply because AMD is supplying the hardware for consoles.
On the CPU front, Jaguar is the successor to Bobcat, which was meant to compete with Intel's Atom
processors. From the get go, it's a low power, but very low performing part. Even in multithreaded situations, even a low voltage laptop processor with fewer cores will cream it (http://www.anandtech.com/show/6974/amd-kabini-review/3
). And while developers may make low level optimizations to Jaguar, this will only work for Jaguar because it's still a different core architecture from AMD's desktop offerings.
On the GPU front, it's still the usual "batch up a bunch of jobs, throw it into API, API makes necessary driver calls". So it's really up to AMD to make the optimizations here, not the game developers. Unless AMD gave free reign to Sony and Microsoft to develop their own drivers for the system, then it's up to Sony and Microsoft.
In any case, the other thing is that what console gamers demand performance wise and what PC gamers demand. For high quality visuals, developers are fine with 30FPS on consoles. But the "PC Gaming Master Race" demands 60FPS. While I'm sure the GPU in both consoles is up to snuff, it's the CPU that's probably going to be dragging the system down a bit.