Yes, even I had heard of and used Wikipedia as a quick reference tool and managed to successfully side track myself on occasion. I have also read some of the literature with regard to accuracy and amendments and so know to check if I require particular information like a date or a location.
Wikis provide a method of collaboration. a way to share information, documents and, as the video showed us, what needs to be done and who is doing what or what is finished. I think there is potential for libraries and quite a number use them. Most seem to be large libraries and the information they provide varies. Most seem to think it is a good way to keep an up-to-date staff manual, others are more adventuresome. My concern is that anyone can edit the documents and this could lead to abuse by users. I think what we use Wikis for needs careful thought, but it is another way of communicating with our users.
Yet again I think this is not for us. Large and split site organisations could well benefit. I was interested that TeachMeet had a Wiki for signing up to attend. I did not realise this when I was looking at it and it shows another use.