Wikia's wiki-style forums were developed some time after this wiki was set up. New Wikia wikis get two forums by default, but those of us who contribute to the older ones have had to create our own. I see a few forum-type pages (in addition to this page) in the Forum namespace, but without the standard headers and linkages and listing of recent items, though you do have http://religion.wikia.com/wiki/Template:Forumheader/Watercooler, which is a start.
I wonder whether the contributors here are fully aware of the usefulness of the system. See Help:Wiki-style forums to get a set of forums off the ground.