I also found the chat a useful way to get out some of my ideas on this topic and here is what I came up with:
Consider EpicAdvice (the WoW SE 1.0 Community). Now ideally the people this community wants to attract are the members of websites like Elitist Jerks. People who REALLY know WoW to the point where they can "calculate the theoretical maximum damage a DPS dagger rogue can do while spec'd into subtlety." They want these people because they have the specialized "tribal" knowledge that will answer the really esoteric questions.
Now consider the kinds of questions these Elitist Jerks will be attracted by. They are not the "What are good quests like X" questions. A question like that is not interesting to them because there are too many answers to it and they are mostly subjective.
The reason Epic Advice has not taken off but Elitist Jerks has is not because people can get answers at Elitist Jerks, but because they can get good questions (EJ has a fairly draconian moderating policy). "What are games like Heroes of Might and Magic?" is not such a question.