You seem to be just about the only person left that thinks GT6 will be on PS3. Things change and Kaz also said he didn't know whether GT6 would be PS3 or PS4.I think you guys should all calm down. The Prologue is obviously for GT7.
Kaz said a long time ago that GT6 was based on the GT5 operating system and it was just a matter of building new apps. One, of course, being the gps toyota 86 data logging app which they said would be released in 2013.
That GT academy winner saw parts of the game a long time ago. It had so many tracks that his hat fell off. What exactly was he looking at a yet to be released devkit or a PS3?
They just shipped the new platform devkit not too long ago.
Of course they are working on a prologue. Gran Turismo 7 Prologue. They have to build a new engine for the new gpu/cpu/hardware for the next generation of Gran Turismo. When they get it working they will release it to as a prologue to hold us over for the (probably really delayed) release of GT7 which will probably be disappointing to many people just like GT5.
So then we will be able look forward to the much improved release of GT8 on the PS4, just like we are looking forward to the release of a much improved GT6 on the PS3
There is simply no window left for a PS3 game, not with next-gen announced in 6 months.
Also they don't need to build a new engine for PS4 no matter what tech is in it, all good game engines are cross platform/architecture and the GT engine will be.