"Wisdom of crowds" is one of those fads especially online and I think there's a myth to dispel. Opinions, concepts, software, decisions and content may emerge and get build as a result of adding-up the individual inputs of many people, but that does not mean that where one identifies group phenomena there's necessarily intelligence, let alone wisdom. Since I think words are important, let me get back to the basics of what the word "wisdom" actually means, referring to a definition quoted from dictionary.com:
quality or state of being wise; knowledge of what is true or right
coupled with just judgment as to action; sagacity, discernment, or
2. scholarly knowledge or learning: the wisdom of the schools.
3. wise sayings or teachings; precepts.
4. a wise act or saying.
While there are cases in which the collective intelligence of many participants to a process of creation or evaluation may yield positive results, I believe there are conditions for that phenomenon of collective emergent intelligence to actually take place and I doubt it should be called "wisdom". And I doubt it's relevant to characterize any group behavior as "wisdom of crowds" as some people tend to do. Since there are a couple of business ideas out there that rely on the assumption that collective intelligence can be exploited by merely putting together a community of users, I think there are quite a few entrepreneurs who should think this through. Sometimes crowds are just dumb and there's nothing very wise about herd mentality as shown in this excellent story of Gaston Lagaffe (click to enlarge).