From Shirky's Essay on online groups: "The Wikipedia right now, the group collaborated online encyclopedia is the most interesting conversational artifact I know of, where product is a result of process. Rather than "We're specifically going to get together and create this presentation" it's just "What's left is a record of what we said."

When somebody goes to a wiki, they are not oging there to discuss elementary questions that have already been answered; they are going there to read the results of that discussion. Isn't this basically what the OP wants?

Why aren't we using the wiki more? We have two modes of discussion here: discussion board, and wiki. The wiki serves more as an archive of the posts that make it to main-page level, meaning that all the hard work of the commenters in the discussion boards is often lost to the winds of time. (Yes, some people have exceptionally good memory and link back to them. But this is obviously not sustainable.) If somebody has a visionary idea on how to lubricate the process of collating high-quality comments and incorporating them into a wiki-like entity, then I suspect our problem could be solved.