It looks to me like the majority of the people who are upset are the hardcore RPG crowd. Yeah there is a lot of changes, but I hope it will still be an enjoyable experiance none the less ^^
Speaking of experiance, there is none, that I've seen so far anyway. It looks like you only level up your weapons. Also everyone talking about how linear the game is and showing maps of jus straight line areas made me think of FFX, and thats not too far from what it turns out to be. I'm still only in the first area but it reminds me so much of the first area from X.
The thing I'm most happy about though is that the pretty violin music they always played in the trailer is the normal battle music so you can hear it a lot, all though the battles usually finish before the good part starts
More later~