For more than 50 years, Americans were drawn to the suburbs, with their sylvan promises of easy living. Owning your own home with a car in the driveway and piece of lawn was seen as central to the American dream. But the latest census numbers show a reverse migration into the cities. Real estate is more valuable there, and even big box retailers are setting up shop downtown. Is this just a Sex and the City trend or is it really goodbye for good to Ozzie and Harriet?