NPR carried a news story on collaboration and collective intelligence. I tracked down the foundational research on the National Science Foundation web site and in a serious academic journal called Science.
In a study involving 699 individuals, a general collective intelligence emerged. Interestingly enough, this general collective intelligence, or C-factor, was not linked to average or maximum intelligence of individual members. It was linked to average social sensitivity, equality of distribution in turn-taking and in the percentage or women in the group. For more information, see
National Science Foundation (NSF) News - New Study Validates Factors That Enhance the Intelligence of a Group http://www.nsf.gov/news/news_summ.jsp?cntn_id=117795
New release includes a great photo of a team working with LEGOs.