MediaWiki is a great choice for a centralized knowledge base. Is there a chance that the talk pages could be opened for discussions/comments/suggestions similar to how MySQL and PHP pages are (see e.g. http://dev.mysql.com/doc/refman/5.0/en/select.html and http://www.php.net/manual/en/language.functions.php?

Not sure if that makes sense in relation to the existing knowledge base and forums though. What's the separation of concerns for these areas?

Looking good Mitch!  Very nice placement of everything to get a searcher started.

You are right about the spam.  Without moderating every submission you'll be full of spam with no room left for real food and who has time to moderate that much stuff?

Yeah, I'm afraid that you don't want to give the general public (or even registered LP users) a pass to post stuff. You'll be spending 36 hours a day just cleaning out the e-graffiti. Even Wikipedia has had to restrict editing access to a large chunk of its entries, and will eventually have to close off the rest of it. It's too bad that so many Web users are so infantile. Maybe something could be done to allow registered LP users to post once they have proved themselves in some way (minimum number of posts, no valid complaints against them, not on blacklist,...).