From Salon:
These days people are living longer lives than ever before. Ancient Romans expected to live an average of 25 years. Today, thanks to advanced medicine and nutrition, the worldwide average is 64. In all, we will enjoy 250 billion more years of life than if we had been born a century ago. Few people, of course, would argue that's a bad thing — but, as more and more people get older, it means that our world is about to undergo some very dramatic changes.
According to journalist Ted C. Fishman's new book “Shock of Gray,” those changes are already being felt in parts of the world. By reporting from cities that are ahead of the overall aging curve, Fishman deftly forecasts the larger problems that will soon consume the globe. Professionals and skilled laborers will be pushed out of their jobs before they can afford to retire, forcing many into service industries that pay a small fraction of their former salaries. Rural communities will struggle with acute aging as young people leave for the cities. That in turn will create opportunities for immigrants, thus accelerating globalization. Builders will need to accommodate more people with greater mobility issues, which will drive up costs for infrastructure. At the same time, scientists will continue to tweak the human life span to the point, perhaps one day, of near immortality.
More here.