As I see it there were three big differences between the launch of 3e and now.
First: The growth of the internet has brought even more people into contact via the message boards. So you have many more people with strong feelings one way or the other.
Second: A good portion of the community had either walked away from the current version (2nd edition), or house ruled the game beyond recognition due to the lack of support that TSR had left us with.
Those two things together left us with a much more fractured community, so when you looked online you had less people expressing the same view point as yourself, and would get less worked up.
Third: Back in 2000, we had not seen much in the way of enhancements to the core game in a good number of years... Heck we weren't even sure if D&D would really continue to be supported under WotC.
Today things are different. The community is more unified. In general we all like 3/3.5e and we think the system still has quite a bit that could be offered. We know the warts to the system, and we know how to work around them. So there's more cost if something goes wrong. Deep down I think every of us has asked, What if we hate the new edition? How much worse will our game be if we no longer have support for the game we love so much?
That fear together with the lack of details about the new system is driving much of the negitivity you hear expressed on this site.
Our group is planning on doing exactly what we did with 2nd and 3rd edition. We will all buy a players handbook, and try out the core system for a few weeks. If we like what we see, we switch systems. If not, we go back to 3.5 and continue to play it as it was. None of us seem very concerned due mostly to the fact that we all basically skipped 2nd edition... We all learned you grab what you want from the new stuff and build your own crunch to make it fix the older edition.
As I see it in the end this is a game about getting together with friends and having fun. And if a new edition or supliment gets in the way... Skip it. The best and most powerful feature of the game is: "The rules only exist as agreed by those around the table." And that fact will always be edition proof.