More important than the influencers, the researchers found, were the influenced. Once an idea spread to a critical mass of easily influenced individuals, it took hold and continued to spread to other easily influenced individuals. In some networks, it was far easier to get an idea established this way than in others. The entire structure of the network mattered, not just the few influential people.

Läs mer: Math Trek: The Power of Being Influenced, Science News Online, Jan. 5, 2008

The theory goes that when opinion leaders adopt an idea, lots of other people quickly follow. Sort of like a 'leader of the pack' theory. Researchers Duncan Watts and Peter Dodds wondered whether this was really the case, or whether instead, large numbers of people would embrace a particular idea when a certain number of their more easily influenced peers started to champion it. More of a 'birds of a feather' theory.

Läs mer: Mind Hacks: Opinion leaders impotent in ideas economy