An excellent recent article in the Economist on the transformation of American suburbs. Some excerpts:

In 1960 fewer Americans lived in suburbs than in central cities or the countryside. Ten years later the suburbs had overhauled both; by 2000 they contained more people than the cities and countryside put together.

...the white population of big-city suburbs grew by 7% between 2000 and 2006. In the same period the suburban Asian population grew by 16%, the black population by 24% and the Hispanic population by an astonishing 60%.

As the suburbs become more mixed, some inner-city areas are turning less so. Los Angeles ... and New York ... both added whites and lost blacks between 2000 and 2006.

...the Brookings Institution ... calculates that 45% of the jobs in America's 100 biggest metropolitan areas are found more than ten miles from the downtown core.

The popularity of such confections [outdoor lifestyle retail centers] suggests that Americans want to spend time in places that look like cities but feel like suburbs. They hint at a broader pattern: cities and suburbs are converging.

Since 2001 the number of violent crimes in suburban areas has risen by 10%, according to the FBI. ... it is a poor record compared with America's big cities, which have cut violent crime by 17%.