More than half of the world’s population is now urban, a famous factoid. City boosters tend to play fast and loose with this statistic, as if it represents the triumph of the city, and more than half of the world’s population now lives in a combination of Manhattan and Singapore. Of  course, they don’t. The majority of urban Americans either live in suburbs, or in new cities–Phoenix, Seattle, Houston–whose character is distinctly suburban. Nevertheless, Richard Florida’s article in the October issue of the Atlantic segues from global urbanization to the virtues of density, closeness, and human interaction in concentrated cities. The so-called creative classes, he writes, “cluster and thrive in places where the conversation and culture are the most stimulating.” This may or may not be true, but the article is illustrated with a two-page map of the U.S. dotted with the major cities. Each city is indicated with its average income. The incomes are high, more than  $60,000 in San Francisco, $54,908 in New York City, and $46,230 in Philadelphia, where I live. Except that the median household income in the City of Philadelphia is actually closer to $30,000. The figures on the Atlantic map are not the average income for cities but for metro areas, which in the case of Philadelphia include the well-to-do suburbs, in which people live and work. I don’t know if these suburbs are the scenes of “stimulating conversation,” but they are definitely neither dense nor concentrated. Neither is San Jose, Marin, or Palo Alto, or for that matter, the outer boroughs of New York City or northern New Jersey. So people are thriving, just not exactly in the places where we imagine—or would like to imagine.