Since its launch less than a decade ago, Facebook has exploded. Today, more than 750 million people belong to the site, sharing photos, status updates, and links with their Facebook friends. The site has even changed how we talk, adding new meanings to the words "friend" and "like." We've seen other social sites rise and fall, but maybe Facebook is different; maybe it's here to stay.
The US is particularly miserable at putting aside money for the future. Should we blame our paychecks or our psychology?