sure they've spent many many millions on these engines, but I think it will be for the best in the long run.
The great thing about the PS3 design appears to be it's scalability, with the possible exception of the RSX.
This means that all the PS4 would need to be is a beefier PS3 with perhaps a faster Cell with more cores, more and faster RAM, bigger HDD's to work with. Essentially allowing the use of PS3 engines to work with PS4 should in theory be not much of a problem, perhaps just needing tweeks here and there and the inevitable improvements these engines go through in time.
This will allow more games to be made more frequently than on the PS3, no more weak software at launch blues.
expensive engine now = cheaper development for the future imo
Proud Sony Rear Admiral
