I'm not a big fan of LG myself, so to people complaining about RPGA changing, I'm tempted to say: It's your own fault.
Anyway, the biggest problem I have with 4.0 is that they had to change the fluff as well. How can you expect coherency in your background if suddenly Tanar'ri and Baatezu get a whole new background, the planes suddenly change (Why drop the fantastisch idea of the Great Wheel??) and monsters cease to exist from one day to the next? I'm not opposed to fluff-changes, but incorporate them in to the storyline. I'm thinking of how Gamesworkshop incorporates the results of the live-campaigns in it's ongoing story, of they way the Lady of Pain dealt with the factions.
It shows that they don't take it very seriously from a gamer's perspective. From the buisiness perspective, I think they know all to well what they're doing.
From what I've read about the crunch aspect, I think it will be for the better. The idea that race would have a bigger impact, for instance, is quite appealing.