Wikis - Hmmm

Having been drilled to the point where "Don't trust wiki sites!" acts like an automatic shield, it will take me awhile to conquer that ideology and update my view. However, exploring some suggested wikis such as SJCPL's Subject Guides and Meredith Farkas' WhatILearnedandWhatI'mDoingWithIt wiki has started to turn me around. I can see right away that wikis are easier to change and expand than a traditional web page; they can be used to link to sublistings in a catalog (I loved SJCPL's Harry Potter Page, having just pulled an all-nighter reading the last book). I also see a similarity between wikis, blogs and bulletin boards (discussions/forums), though in purusing various wikis I see one really cool difference; that of being able to link to sites offering more information about the topic(s) featured on each wiki page. It's better than surfing, or hit-and-miss searching, because the links are posted by people following the same lines of interest.
But, just when I get rolling, a visit to the MarylandLibrariesSandbox shows the true problem with wikis; the first thing I see is: "Here's the BAD news... someone edited the HOME page for our wiki and deleted all the labels that linked to all the pages that belong to other folks."
My understanding of wikis is just what happened there: anyone can visit and change it. Anyone can post information. Unless the owners of the wiki are vigilant, there is a potential for a great deal of damage. So, Wikis seem to be a good way to share information, but still, hmmm.