There's a couple of issues with forum mods
1. Mods need testing, and many are imperfect
2. The JFusion plugin for joomla isn't compatible with the ones I've tried so far
It is being worked on but im looking at several options to add this feature

Regarding wikia, we use Joomla which is a CMS capable of similar functionality. We just need some people to write articles, etc. Its just a case of setting up the permissions for the authors so we can keeps tabs to make sure we don't end up with unsuitable content posted on the site. If people are interested, just drop me a mail.