You can use an "account_creation_password" to help limit who can get an account and edit the new wiki. That helps keep out spammers.
Maybe add a horizonal rule <hr> between end of content and the wiki path and ikiwiki links at bottom of pages. See http://www.shiningsilence.com:81/hammer/ has the ikiwiki links in the middle of some content -- maybe move that real content up. As an idea use a slightly different template for the pages that can be edited by anyone (once they get account) and the few pages that are locked and can only be edited by a few (like downloads page and front page). ikiwiki is a good choice. (The main thing I don't like about ikiwiki is that there is no discussion mailing list for ikiwiki -- have to use the ikiwiki website Discussion.)
