There is no need for me to live in a city. I work from home and telecommute. I travel to a city that is 45 minutes away for pleasure. He was 100% on from my perspective.
If telecommuting does become the defacto mode of work, I expect people will live in a greater variety of places. For instance, I wouldn't mind living a few years in Europe and Asia.
Cities open more of what Steven Berlin Johnson calls "the adjacent possible" in Where Good Ideas Come From. As I said above, if you're interested in knowledge spillover effects promoted by cities, see Edward Glaeser's The Triumph of the City.