Ed Glaeser has written on the enduring advanages of New York City; Joel Kotkin has been writing about the advantages and the re-bound of areas in what many once called "fly-over" country. Both make good points and both phenomena are also complementary.
Economists know all about specialization and diversification and how these are dynamic and subject to innovation. They also know about the charms of amenities (natural in California and cultural in New York).
Ever cheaper and ever better communications opportunities are the new normal and we get "The Network Society". The label is not mine, but the title of a piece by the amazing Peter Drucker in the March 29, 1995 WSJ -- which I have clung to for classroom use.
Drucker saw that, "In 10 or 15 years, organizations may be outsourcing all work that is 'support' rather than revenue-producing, and all activities that do not offer career opportunities into senior management."
Not the "death of distance", but the ever changing ways in which distance costs, communications costs and transactions costs re-shape the world.