"[T]he kinds and amounts of innovation available to a person vary significantly in urban and suburban and rural America, and the degree to which they vary is increasing rapidly. Some of those variations are really obvious: you can't get cellphone coverage everywhere in rural America, much less broadband, for instance.
But a whole other major class of innovations, which has to do with the layering of infotech over place, is less noted but sharp and clear once you look. Mapping aps like WalkScore, smart grids, car-sharing and product-service systems, place-annotation systems like Yelp and the like all seem to both make more sense in wealthy urban environments, and to be taken up more quickly into the culture.
And, as we've remarked here before, all things being equal, people who live in compact communities tend to keep more of their paychecks as disposable income and spend less time commuting and running errands, meaning they have more money and time to buy gadgets, experiment with innovative tools and update their systems... thus perhaps fueling more and faster innovations.
Or at least so goes the theory."