If GT6 sucks as much as GT5, if it is as inconsistant as GT5, if it shows that PD still has no vision for their franchise...then I'll turn my back on PD and see what T10 has to propose.
To me, GT6/Forza5 could be like PES2012/FIFA12...the one that kills fans devotion. Yamauchi could do to GT what Seabass did to PES/WE. Seabass kept saying that they heard the fans and that they would completly rethink their game... but that was pure lies. With GT6 we will definitly know if Kaz is able to put himself into question.
But I would never underestimate Kaz's capacity to make completly wrong/stupid decisions. As a fan of GT from the very first opus (I imported all the games from japan and then rebought them when they came out in Europe), I am fed up with PD's ambiguities in their communciation (we did not know for sure if there were damages in GT5 one month AFTER the release!!!), fed up with his unability to admit GT5's flaws, fed up with the game grinding focus, fed up with Kaz speaking like some kind of cryptic jedi master that says everything is possible...and then never delivers anything, fed up with the lack of community manager, fed up with reading Kaz say he wants nothing but the best and most accurate simulator... when so many things in the game say the contrary, fed up with fanboys defending the guy no matter what, fed up with untested updates that need a patch, fed up with arbitrary game design decisions that make no sense, fed up with the game design and art that is less fun that a surgical unit, fed up with this pompuous style that is supposed to be classy and stylish when in fact it is just boring and completely uninspired, fed up with having to wait 3 minutes and press 25 buttons just to change my car...God this game is soooooo unthought and broken it's not even funny.
To me, as for many many fans i'm sure, GT6 will be the last chance i give PD to get back on track.
Otherwise, I'm more than ready to buy the next Forza.