The New York Times has an article about the U.S. State Department's Diplopedia. Eric M. Johnson of the State Department’s Office of eDiplomacy shared his learnings during the Wikimania conference in Egypt (video accessible if you use Internet Explorer, sigh).
The art of diplomacy excels with shared context that wikis can support. And while fundamentally State may gain productivity, particularly if they allow it to work across agencies, evolving from manufacturing era cable systems could evolve culture itself:
There was a larger point to bringing his message to Wikimania 2008, as the annual conference is called: if wikis can work at the State Department, with its fabled bureaucracy and attention to protocol and word choice, they can work anywhere.
There certainly is a culture of collaborative writing at the State Department, Mr. Johnson acknowledged: memos are drafted, massaged, passed up the chain for comments and then approved. But this form of collaboration is based on the notion that the more people who read something, the less chance it will be candid. Wikis, by contrast, are collaborative only in retrospect — someone has to be prepared to be the first to write something, and deal with having those words changed by a complete stranger.
Mr. Johnson said his office occasionally gets calls from new contributors: “People will say, ‘I have something I want to post; I want to check before I do it.’ And we say, no, no, put it up.”
The decision to embrace wikis is part of a changing ethic at the department, from a “need to know culture” to a “need to share culture,” said Daniel Sheerin, deputy director of eDiplomacy, which was created in 2003. “This is a technological manifestation of a policy difference,” he said, a change he dated to when Colin L. Powell was secretary of state.
Emphasis mine. I'm not sure I would say that wikis are not collaborative in retrospect. They are in prospect, when words first written find collaborators and it turns into collaboration when their is a shared bounded goal.
Back when I worked in this sphere in Estonia, they didn't have legacy infrastructure and culture. I set up a Lexis Nexis account, ran persistent searches on diplomatic topics and sent out a newsletter daily by email. In retrospect, it was a form of blogging. If only I had the tools I have today.