a wiki needs a community. You need people to think "yes I want to add this data to the public wiki" when they see something. This is easier with the general arts than it is with code. Emacs is a good example of how great community documentation can be, and how such a project should be moderated. Initial stages of public documentation are always messy. keeping it that way lets more people get involved. later you want to aggregate info and organize all of that together. this is what I've seen in the jsoftware wiki, (and k wiki, which has pretty much 99% of its work completed by me).