I'm actually quite a fan of "Wikipedia" -- often find more information here than elsewhere -- especially on obscure (historical) topics. I love it's layout -- it is clear and easy to navigate with links to everything, so always a great adventure to be had! Am concerned about its "authoritativeness" but use it in conjunction with other sources where possible.
There are several uses for Wiki's in the work environment. I love the ideas of using them for "subject guides", book reviews or catalogue annotations and as an online community directory. Great how anybody can add links/comments and "prune" out of date/dead links.
I didn't know that access can be restricted (I thought this contradictory to a Wiki) but can see there might be instances when this is useful.
Had a look at the three examples.
1. St. Joseph's. Edited by library staff. Loved the Subject guides -- like what we used to call Pathfinders but oh so much more! -- with book reviews, databases and internet sites and clubs listed (if relevant). And loved how the book etc links took you straight into the catalogue! Very impressive.
2. Princeton Public Library Booklovers Wiki. This was also great with book reviews and author information -- also "enotes"/study guides. Very impressive also! PS Great to see this technology hasn't forgotten about "Books"!
3. Library best practice. A great source of information for staff covering every (?) conceivable topic!
4. Examples for libraries. Fun to explore and see how they could be applied.