The Chartered Instituted of Public Relations (CIPR) released its first edition of guidance for use of Wikipedia last week. See the full guide in PDF form here. The standards are a collaborative and still on-going effort that includes input from both public relations professionals and wikipedia editors (whom someone has decided to cutely call “Wikipedians”) and has been endorsed by similar organizations in Canada, Australia and the Public Relations Consultants Association, a British organization similar to the CIPR.
You can see and even participate in future collaboration on this project on their project Wiki.
Buy the book!