This is an interesting discussion. Coming to ENWorld as someone who was on Usenet, many times I say "what's all the fuss about?"
But still, we have "no politics," "grandma friendly," and "no attacks on a person," as rules, and that's fairly effective.
The real problem that I see is that there is a significant amount of the core ENWorld audience that simply doesn't like 4E and is still looking for a direction to go to for future games, now that 3X is out of print. When I say that, I'm not talking about the "drive by" posters who come in, make some flames and then leave, I mean the core membership who have been here since the beginning. I don't know if people realize it, but I am one of those people, so I recognize the original crew most of the time, and put a lot more stock in what they have to say.
I think for a lot of them (and me, partially, although I am playing 4E I have a lot of issues with it) are frustrated because they've been on board the train for a long time, and it has gone in a direction they aren't comfortable with, leaving them without a game in print that they support. It's only natural that you see some acting out because of that. Is it a good thing? No, but when you actually call these folks on it, they're generally reasonable and stop. In these cases, I think peer pressure is the way to achieve better results.
But on the other side, I think a lot of folks who are upset at the claims about 4E really need to relax a little more as well. To take the "video game" quality, you see a lot of drive by posters using it, and moderation typically steps in and deals with the offender. At the same time, there are a number of qualities of 4E that you can legitimately argue are video gamey. Note that I'm not saying they are that way, but that the issue is up for debate.
For me, it comes down to "is this thread a legitimate conversation, and can I bring something to it/learn something from it." If the answer to both is "no" I just stay out of it. I also try to remember that even if the posters tells me otherwise, everything on message boards is only the poster's opinion.
So that's my $.02 worth.
--Steve