The wonderful world of Wikis

I know I should have resisted the temptation to write a cliche masthead, but didn't.
This is my second try as my previous posting vanished in the colour and movement I've had with the You-Tube posting! Wikis would be a very logical application in the public libraery environment, especially for Book groups, a la the Princeton Public Library example in the listing on the 2.0 training pages. I've had limited experience with such groups but the occassions on which I have moderated our local Book Chat group have been most enjoyable working hours with a group of very interesting people such as the lady who had encountered Francis De Groot of Harbour Bridge Opening fame or the Italian gentleman with vivid memories as a child of the Nazi occupation of Rome. A Wiki would enormously extend the opportunities for sharing that such a group offers, and provided everyone involved was happy to "go public" , would be a most entertaining, enlightening and interesting feature on any library's webpage. Local studies is the other area which could be interesting as in the examples from Montana and Wisconsin. I guess the only risk would be what people might say (some of our Book Chat people can be very passionate),but I guess it can be edited and there's no point ,it seems to me, to have a wiki that people can't directly contribute to, you might as well leave it as webpages.