Anyway, I've been reading the Paizo forums, and the Concerns & Criticisms forums at the WOTC boards, and I've come to a number of realizations, resulting in this morning's epiphany.
The way they're marketing this change is to very slowly and carefully poison the well, by occasionally pointing out a 3.5 mechanic which doesn't work, has never worked, and they're not going to fix. As it so happens, the things they have identified have been things I've had problems with in my campaigns, so it's mostly not new information, and the only unwelcome part is when they point out that these issues are so integral to the game system that they can't fix it without completely changing the game system and if you thought people were whining about a 4.0 upgrade, how do you think they'd complain about 3.6? Yikes.
So, I don't have a problem with that. What I have a problem with is that they're proposing to release a new version of the game system which I may not want to run. Also, not so much of a problem with that--other game systems I've played and enjoyed have evolved outside of the sphere of my enjoyment. However, if they do that by first making me not want to play 3.5 any more... that's not so good.
Anyway, the big epiphany of this morning is that if they release 4.0, and it's similar enough in rule system & concept that I can use all my 3.5 supplements with it, I will feel absolutely no interest in buying any 4.0 supplements. On the other hand, if they release something so different from 3.5 that 3.5 stuff can't
be used with it, then they will have written an entirely new game system that I may have no interest in playing, in which case I will also feel no interest in buying any 4.0 supplements.