I'll publish my findings here
Of course the biggest reason many are using against GT6 on PS4 is that PS4 has not sold any consoles yet, so at the moment there are zero consumers for a GT6/PS4, whereas there are 70 million possible consumers for a GT6/PS3.
This implies that GT6 MUST sale around 10M units again in order for it to be profitable for Polyphony Digital, and in order for GT6 to fund the development of GT7.
Is that really true? No, not at all.
In 2008 Polyphony Digital solid 4.12M copies of Gran Turismo Prologue. Thats more then any Forza game outside Forza 3 (5.37M). In 2010 they sold 10.39M copies of Gran Turismo 5. If you add those sales together thats 14.51M copies of Gran Turismo sold on the PS3. Thats not including the nearly 3M copies of GTPSP sold
I'll put this in perspective
Total number of exclusive games sold on PS3 per franchise, and the Forza Franchise (3,4, plus Horizon)
16.61M - Uncharted
14.51M - Gran Turismo
10.71M - Forza
9.08M - God of War
5.36M - Killzone
So how exactly is Polyphony Digital bleeding for so much money that they must release on the old console again? Its the old double dip routine. Get the consumer to pay for the inferior product now (ex: DVD with no extra features, no 3D, no extended scenes) then down the line, in a year or two, release the better version (all features, extended scenes, etc) which the faithful fans will no doubt buy again.
The "there are zero PS4 consumers" story is absolute nonsense and marketing speak for several, obvious reasons. I do agree a launch GT6 on PS4 wouldnt be the best decision, but still a better decision then a GT6 PS3 around the same time. A Q2/Q3 2014 or even Q4 2014 release of GT6 On PS4 would have been the way to go. Once the initial hype blows over and the PS4 needs an extra pair of legs to keep going GT6 could be there to pick it up.
They did the same thing with Gran Turismo 3, releasing the game just 8 months after the North American and Europe Playstation 2 launch. And Gran Turismo 3 is far and away the best selling Gran Turismo title of all time. GT6 will be the worst selling, easily.
So what changed this time? Why are they not looking to replicate the success of GT3? They think they have the fanbase, hook, line, and sinker, and that they will follow and approve whatever choice they make. Polyphony Digital's announcement could have been a black background which said in white lettering: GT6, Coming to PS3 this Holiday season, and all the fans would have been just as happy. Buy inferior game now because it offers instant gratification at just $60, then buy what the game should have been now on PS4 in 2 years.
Just look how many apologists are on this very website. They say once again they'll give us garbage damage that would be passable on a PS1 game. The fans response? 'We dont care about damage'. Once again we hear bad sounds. The fans response? 'Its not as bad as it seems'. Instead of expecting excellence, or even just improvement, their standards have dropped to rock bottom. What they dont know is that will only help ruin the franchise.
People are starting to catch on
Gran Turismo North America Sales
GT3 - 6.85M
GT4 - 3.01M
GT5 - 2.59M
Gran Turismo Japan Sales
GT3 - 1.87M
GT4 - 1.10M
GT5 - .80M
With standard cars, return of poor damage, sound, a handful of new tracks, minimal new car increase when compared to the competition, competition from next gen racers, and being an extremely late gen release all means GT6 wont get great reviews. Reviewers will see it as and even call it GT5 XXL, or even GT5.5. It will pretty much lose its AAA status as a franchise and will no longer be a true console seller.
All this because instead of shooting for the stars and excellence and being in the forefront of innovation, they decided to turn the series into a cash cow. The problem is, unlike other cash cows in gaming, Gran Turismo is no longer fun, and it will belly flop like Louie Anderson.