I just deployed privilege wikis to meta see: http://meta.stackoverflow.com/privileges
This is in response to the ever so popular, you have gained a power request.
Temporarily we are allowing all users on meta with more than 2000 reputation to edit the wikis, we will then use these wikis as the global default wikis for all sites.
Generally we would like all the wikis to be approachable and clear, they should cover everything a user who hits the threshold should know. A screen shot or two may work in some cases.
500 hundred arbitrary meta points go to the most awesome contribution