When Wikia Search was first released, it was dismissed by Mike Arrington at TechCrunch as one of the most disappointing products he had ever reviewed — primarily because it just added social features such as user profiles on to a rather lame search tool (powered by the Nutch engine). I had to agree at the time. But this alpha allows a user, through the wonders of Ajax, to click and edit in place any one of the search results, including title and description, and even allows search results to be completely deleted. You can also add new URLS, and pull data from a preview, which also appears in place.
Obviously, this is wide open to abuse — in much the same way that Wikipedia is. In fact, it’s even easier because you don’t have to click to go to an incomprehensible “edit” page with weird wiki commands for links. You just click and edit. Whether Wikia Search can develop the same kind of community of editors and overlords that Wikipedia has, which prevent the entire effort from degenerating into outright anarchy, remains to be seen. But it’s an interesting experiment, I think.