Wikimedia
Wikimedia Foundation is a private tax-exempt corporation (IRS 501) in the US founded by Jimmy Wales aka Jimbo. It has an independent board that makes the decisions as required by law.
Wikimedia is funded by donors, and spends virtually all of it's money it receives as donations on providing hardware for MediaWiki sites such as Wikipedias and Wiktionaries. There are no salaried employees at the present time, and no immediate plans to have any.
Most longstanding participants in the Wikipedia project have greeted the formation of the nonprofit with great enthusiasm, and plans are in the work to set up nonprofit organizations in European countries to complement the global foundation. Jimbo has given all rights and ownership in the Wikipedia name(s) and websites, as well as some hardware, freely and permanently.
One of the greatest difficulties that Wikipedia has faced is in maintaining an open and welcoming culture in the face of repeated attacks from vicious trolls, such as the ones now beginning to plague Consumerium. Wiki management issues are complex and difficult, and there are many lessons yet to be learned.
The incredible success of Wikipedia shows that it is an excellent model for any community organization. Wikipedia faces far greater challenges than any single-purpose community such as consumerium, because by design, it draws from a very broad range of ideological backgrounds, and must be welcoming to them all. Consumerium, or other narrow-purpose projects, will likely find a more homogeneous user base, thus making governance decisions much easier. By applying the lessons learned at Wikipedia, great success is likely.