Are we here to preach and make converts?
For me, the answer is no.
We shouldn't be a site for people with out a religious inclination or with doubt yearning for a change to a whole new system. (Blatant hypothetical question "Shouldn't we all be Mahayana by now?") We shouldn't be posting normative declarations in the form of a question. (Blatant hypothetical question "Should Buddhist be teetotalers by now?) And so on for every view ever ascribed to Buddhism. My comment about preaching should apply to answers & comments-- with the exception of advice questions. If someone is asking "What is the Buddhist thing to do about abortion, alcohol, depression, etc" and as they invariably do-- don't bother to tag with any particular school of Buddhism, then an answer is going to be somewhat prescriptive.
We shouldn't be a debate site, there is no independent third party to call a winner, no referees, no ground rules for what constitutes fair debate. Instead, we have Q & A where the winner is chosen by the question asker, or more commonly, not at all. Question askers are likely to pick an answer that suits their biases were they to post a statement for debate. (Blatant hypothetical question "A permanent, non-changing soul doesn't exist-- can you prove to me otherwise?") Maybe some enterprising reader of this post can go make a debate website.
In light of this, I urge people to ask questions with potentially factual answers, or advice questions or the many other sorts questions that get numerous upvotes — and move the preaching to their blog, the debate to one of the many forums that exist elsewhere on the net.
And I descent from my soap box, because this post is getting a little preachy.