If I fork repository joe/foo, and it has a Wiki, I won\'t get the wiki. Right now I\'m just interested in forking the wiki to add pages to it.
joe/foo
If you're making your own wiki that others would be interested in forking, you could do something like we did for the RailsConf 2012 wiki.
We made a local clone of the wiki and then did git push --force to the "code" repository. It gets a little out of sync, but that's easy to rectify.
git push --force