Semantic MediaWiki has been enabled on WoWWiki in order to aid in data-finding. Semantic data is information that the wiki understands what it means, not just what it looks like. In the initial roll-out phase, semantic data is simply getting defined. The usage bit will come later, but imagine the possibilities of automatically-generated loot tables, and npc lists.
Several templates define semantic data using their parameters, and other semantic templates are being written as well.