This is sort of a treatise on the butterfly effect on a sociological scale. While the examples used seemed to spread out in all directions, I think that Gladwell was able to keep everything under one theoretical umbrella, with some wrestling. I'd be interested to see if Gladwell's observations tie into Hierarchy Theory on some level, and I suspect they do. There may also be underlying elements of stochasticity that effect the outcome of tipping point dynamics, though James Gleick would be a better judge of that. All-in-all a very interesting read about outliers, word of mouth, and epidemics.