Neal Stephenson has a wiki
This is awfully cool. Neal Stephenson, author of some of my very favorite books, has a wiki. He set it up in 2003 with the publication of the first novel of The Baroque Cycle, Quicksilver, and it has grown into a kind of meta-FAQ for the whole series (which, if you haven't read it, takes place in highly accurate and incredibly detailed historical context, to which extensive annotations are well justified, even for the historically knowledgeable reader).
The folks contributing to this wiki have made an admirable effort. But Stephenson's introduction to the project shows that he clearly had larger ambitions for his site.
Why put the information on such a complicated system, when a simple FAQ is easier? Because we are hoping that the annotations of the book on this site will seed a body of knowledge called the Metaweb, which will eventually be something more generally useful than a list of FAQs about one and only one novel.
However, Wikipedia. has fulfilled those goals far more completely than this site has managed to do, in terms of its breadth, depth and number of contributors. The dominance of Wikipedia poses interesting questions for other wiki-communities. I haven't made up my mind about how they should work with each other, but my first instinct is to avoid the duplication of effort and to ensure that added knowledge is shared as widely as possible.
It's something of a dilemma: for example, it wouldn't be appropriate to add commentary on the actions of Sir Christopher Wren, the character in The Baroque Cycle, to the Wikipedia article on Sir Christopher Wren, the historical figure. However, it would be perfectly appropriate to have an entry on Daniel Waterhouse, the character in The Baroque Cycle, in Wikipedia.
If I were involved in this project (or any other fictionally-inspired wiki, like the Star Trek wiki I mentioned previously), I would propose two alternative strategies: either create a sub-category within Wikipedia, such as this one for The Lord of the Rings, and focus one's efforts there; or build your wiki as a wrapper around the Wikipedia article, with the ability to add extra content as it applies to your narrow focus. That way, any improvements one might make in the general article go back to benefit the entire community, but one still has a place to make specific mention of those items relevant only within the context of the literary work.
I haven't settled on an answer. But it is an area we should think about and try to determine some kind of best-practice, if only to save many hours of the community's collective effort.