An article on wikis entitled Veni, Vidi, Wiki recently posted on Wired (at two in the morning?) by Ryan Singel might just be a must-read for institutions wary of 2.0 technology and of librarians thinking about how to frame that technology to their administration. I've added the emphasis.
Wikis have also invaded the workplace. After programmers introduced wikis to large companies by sneaking them inside the firewall to manage software documentation, some large corporations adopted wikis for other purposes as well. From entire intranets to small group projects, enterprises are utilizing the power of wikis to enable simpler, clearer communication within a corporation ...
Wikis with the best technical features can still fail if the organization does not fully embrace their use. However, unlike open consumer wikis, in business they are likely to be used in the conduct of work, on specific projects, by people whose own interests are aligned with that of business. This is especially the case if, after the initial grassroots movement, management fully supports the wiki not as an optional, after-the-fact knowledge-sharing tool, but the primary facility to conduct work, eliminating alternate channels. The answer to almost any question has to be "It's on the wiki." Otherwise, depending on the culture, uninitiated employees may ignore this collaborative tool in favor of old habits.
Ironically at my own institution the catchphrase "It's on the Library Manual" has already taken hold with the library staff, and efforts to migrate the information from there to a wiki are already underway.