Ideally in my view would be a wiki manual with restricted editing rights, Autodesk's new Help Wiki (
http://wikihelp.autodesk.com/Revit/enu/2012/Help/Revit_User%27s_Guide) is set up so anyone with an Autodesk account can edit them but the changes all get vetted by moderators before they go live. I don't know if there is an open source version of this solution but know that php.net also has a good solution (
http://www.php.net/manual/en/curl.installation.php). Any logged in user can add a comment and comments get periodically erased (?) or incorporated into the help manual. At least I hope that's what they do with comments...
At the very least I think there needs to be central management on the creation of new pages. Otherwise things get very messy. Look though at the wikibooks structure for mediawiki (
http://en.wikipedia.org/wiki/Wikibooks) which enforces a parent / child relationship between pages - important in a manual if you asked me.
The current situation with a very sparse manual is of course not acceptable in the long term and some method must be found to allow new members to get editing rights. (I've requested an account, but not sure if anyone is looking at requests just now.)
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