I'm not sure what to make of wikis, altho' the concept of using computers for collaborative writing or shared authorship has been around for a long time. I vaguely recollect futurists' predictions of all fiction becoming the "choose-your-own-ending variety," but except as a novelty, that doesn't hold much appeal for me. The power of the wiki, it seems, is as a tool for the types of documents that are already written by committee. Or would have been written by a committee if the committee found it easier to meet. Or maybe not -- maybe there are uses that someone mired in the past can't possibly imagine.
Tried the adding to the "sandbox" at Ambient Librarian, mainly because it resembles Wikipedia, but for some reason I couldn't get it to show a link. (Yes, I just poked around and didn't bother reading instructions).