News hit the other day that Facebook may have lost about six million users in the U.S. in one month, according to Inside Facebook, a site that analyzes the social network for developers and marketers. Facebook has close to 700 million users worldwide, so a loss of six million doesn't sound like much, especially in light of data that suggests the service has been pushing aside regional social sites to conquer large swaths of the developing world, and actually posted a net increase in overall users over the same period.

But a six million user loss is a little more painful when compared to the U.S. user base, which reports say stands around 150 million—or roughly half the population of the country. It's not crippling, but a four percent reduction isn't negligible either. At the same time, the same data source suggests the service is experiencing similar losses throughout the Western world in places like Canada, the U.K., and Norway. Could American audiences finally be turning on the social network?