Daniel Mayer wrote:
This combined with the existence of other much less-successful wiki forks, gives us our only data on the subject. On top of that is the huge momentum behind the Wikipedia brand and the fact that it is very, very popular. This kind of popularity requires a lot of money to keep things running, thus making forks even less likely to be successful.
I think this is likely true as far as a broad encyclopedia goes, although I do think we need to develop some sort of review system at some point, because forks of reviewed/edited subsets of Wikipedia are still very much possible. For example, a group of [X field] academics inspired by Larry Sanger type sentiment might well fork the articles in that field and create a specialty-topic encyclopedia that would compete with us on that subject. (The branding would be about neutral---Wikipedia's bigger brand would probably be a wash with a group of academics' stronger credentials in that particular field.) We're already competing with a few of these that predate us; the online/gratis Stanford Encyclopedia of Philosophy, for example, is probably still a more well-regarded philosophy reference than Wikipedia.
(We do seem to have blown everyone away in mathematics though, thanks in large part to a handful of very good and very prolific Wikipedian mathematicians.)
-Mark