And now more exciting news, SCEA posted a patent application for "DYNAMIC CONTEXT SWITCHING BETWEEN ARCHITECTURALLY DISTINCT GRAPHICS PROCESSORS":
http://appft.uspto.gov/netacgi/nph-...68".PGNR.&OS=DN/20120320068&RS=DN/20120320068
"Graphics processing in a computer graphics apparatus having architecturally dissimilar first and second graphics processing units (GPU) is disclosed. Graphics input is produced in a format having an architecture-neutral display list. One or more instructions in the architecture neutral display list are translated into GPU instructions in an architecture specific format for an active GPU of the first and second GPU."
It seems that they are aiming for APU+GPU combination in PS4. As for architecturaly disctinct graphic processors, they will most likely use 7xxx for APU and 8xxx for discrete GPU... but off course, who knows. Maybe they are just doing preemptive patenting for their patent war chest.
Quoted for the next page.