Dave Snowden captures a key challenge in dealing with groups ("Mass validation of truth has generally being exploited by tyrants in the past and a tyranny can be collective as well as individual."), and links to What's Next: The Idiocy of Crowds: "The effectiveness of groups, teamwork, collaboration, and consensus is largely a myth. In many cases, individuals do much better on their own. Our bias toward groups is counterproductive. And the technology of ubiquitous connectedness is making the problem worse...Bernard Nijstad, a psychologist at the University of Amsterdam, explains that if you take a group of 12 people and have half brainstorm together on a topic while the other six go it alone, all 12 will usually agree that the group experience was more productive--even though those working alone almost always end up with more good ideas."
These comments are reflective of my own experience. For groups to be of value, each individual must be an individual. Aggregation (or the forming of groups) is valuable when we bring together unique people. If we bring together like-minded people, we may end up with the joys of group-think. That's why I enjoy reading blogs. I can aggregate diverse perspectives, and form a representation of the whole...based on many individual opinions. Groups and collaboration are not the problem. The problem arises when a group thinks/acts/speaks with one voice...silencing the unique views and opinions of individuals.