@Phrancheyez
I agree. I can see the PS4 having the same CPU and GPU as the PS3 but with faster clock rates and some extra optimisations, as well as much more RAM and an "innovative" controller.
That way the BC won't be an issue, the costs will be low initially, and 3rd parties will not have problems making games for it. Basically, a PS3.5 @ $300 in 4-5 years
PSN ID: T_Gears
End of 2009 ltd sales:
Wii = 67-68m
X360 = 38-39m
PS3 = 34-35m
Prediction: The PS3 will surpass the 360 on weekly sales after it drops to $299 on all regular weeks (no big releases).