An enjoyable tour through Johnson's musing on the way people and environment combine to give rise to good ideas. I liked the structure of the book, with identifiable themes in each chapter. Most of the examples were interesting, and as usual, I liked Johnson's style.

I did feel the book lagged at the end - I would've preferred not to have the last chapter. This chapter was essentially justification for the rest of book. The mechanism was to show examples of inventions and classify them on a grid, and to claim that the trend that showed up supported his thesis than networked non-profit environments are a better (and growing) source of innovation. Given that Johnson picks the innovations and performed the classifications, I'm not sure it's sufficient justification. Better to have let the earlier chapters stand on their own merits - if we weren't already convinced, we wouldn't be likely to become so.