Zuckerberg's site lost nearly 6 million American users last month, along with 1.52 million Canadians and hundreds of thousands in the UK, Norway, and Russia (though made some gains elsewhere). The Week floats four theories, including "This is just a temporary dip":
"Seasonal changes like college graduations, and other short-term factors, can influence numbers month to month and obscure what's really happening," says Eric Eldon at Inside Facebook. These May figures are certainly intriguing, but let's not overreact. The long-term trends are the ones that really matter.