Richard Florida kindly sites "Does Density Matter?" by Sandy Ikeda and myself in today's WSJ. I have cited our story a few times on this blog. It is Ch 22 in the Handbook of Creative Cities.
Sandy and I each had doubts about a "the more density, the better" view -- which we have encountered many times. The more nuanced "Jacobs density" is Sandy's phrasing, but it captures our "let a hundred flowers bloom" story.
We all want economic growth which requires human capital to be creative and inventive. That occurs when and where people can form the networks that work for best for them. Beyond that, it is very hard to specify the "best" settings. That's what land markets a for. Until we somehow become much wiser, let them be.
Wendell Cox has more re the density confusion.