Gamers like to argue about their games. This is something that has been pretty constant in my experience since I started playing D&D back in the late 80s. Whether it was an argument over individual mechanics or even entire systems, the debates usually began prior to or following play and could last an hour or more (I even had arguments that went on for the entire evening). These days many of the disputes I see are online and over deeper issues like the purpose of RPGs in general, the appropriate way to construct an adventure or run a game, etc. The divisions widen as the stakes and passions rise.
I am not sure that the level of internal hostility this generates is a good thing, it certainly seems the gaming community is more fractured than ever before (when I was younger we were all gamers and we all gamed together, but it feels like that isn't the case anymore). Now gamers are grouped into different camps around specific editions or specific styles of play. Before we grouped people by type (rules lawyer, role player, min/maxer, etc). Sure there was always some division around system (those who played GURPS vs. those who played D&D or Vampire), it just never quite felt as intense and divisive as it does today. The idea of demonizing a person because they happen to like 4th edition D&D, sandbox style play or rules light games has little appeal to me. I consider myself more of a traditional role player, but I don't think it is fun to heap anger on people for perceived "badwrongfun".
And there are real pitfalls to being persuaded by your fellow gamers. How many have gone from knowing exactly what they like and how they like it, to second guessing themselves because they were exposed to some grand RPG theory? I've certainly seen this. Great GMs ruined because they wanted to please some anonymous posters in a gaming forum. They either adopted a strange new method for constructing/running adventures or escaped into an existential crisis over the meaning of gaming itself. To me that makes no sense. Whatever you are doing at the table should come naturally and be a joy, never a struggle. I play RPGs because they are fun and stress-relieving.
Still I like a good debate about gaming and I am no stranger to things like online edition wars. It is fun to argue about the games we love . I find it helps clarify things for me as well. Sometimes it even forces me to change my position (or at least re-evaluate it).
I think what I like most about debates is they expose what you don't know about the subject. You may walk into a thread on character optimization in 3E thinking you know everything there is to know about builds or 3rd edition buff spells, only to have your ignorance exposed by a poster on the opposite side of the fence (and often the revelation is handed down with a heavy dose of sarcasm or flamebait). It can be infuriating when this occurs, however it can also make you a better gamer. Of course sometimes posters are just blowing smoke so you need to check the RAW for yourself when you've been corrected by someone. In my opinion losing an argument is one of the best things that can happen for a gamer, because it forces him to see things he may have ignored before. It is easy to carry around misconceptions about a game mechanic, and I am sure we all do it (I know I have). As long as you don't get to worked up, it never hurts to be corrected by someone.
The secret is to be polite and realize that just because someone has a superior argument to yours, that doesn't automatically mean they are right (jus t that they made a better argument). It is also good to know when you've been beaten (even if you haven't changed your position). There is nothing worse than a poster who insists on having the last word after being trounced again and again. We are all human. At some point everyone loses their temper and posts something regrettable. But if you are cordial most of the time, even to people you disagree with strongly, it will make your online debates fun and productive.