One notable exception is MySpace, which Facebook surpassed in April as the world's biggest social network. The News Corp. property has seen its traffic stagnate both domestically and globally in the last year.
MySpace's flattening growth stems partly from a maturing market in North America, where social networking traffic grew only 9% for the year ending June 2008, according to comScore Media Metrix. Facebook's 38% North American growth even looks sluggish compared to its 153% jump worldwide, for a total of 132 million users as of June.
But elsewhere, social networking is taking off. Consider traffic growth of 66% in the Middle East and Africa to 30.2 million, Europe increasing 35% to 165 million and Latin America rising 33% to 53.2 million.
The comScore data roughly parallels findings presented in April by Universal McCann showing online social network membership in countries such as Brazil, Russia, Taiwan, and Mexico growing at more than 70% compared to less than 49% in the U.S.
Facebook has also benefited from launching an effort at the start of the year to allow users to translate the site into different languages. Last month, the company said it would also begin to allow developers to translate their applications into multiple languages.
MySpace began a push to offer localized, foreign-language versions of the site two years ago. But with only 3% growth in the last year to 117.5 million, it appears to have reached saturation.
Facebook's traffic has grown more than fourfold in Europe, Asia-Pacific, the Middle East and Africa, and Latin America. Its jump to nearly 12 million monthly visitors in Latin America from 1 million a year ago is especially eye-catching.
In some instances, Facebook's impressive stats abroad result from having a small base. Its growth tripled in Japan over the last year to 538,000 visitors, but Facebook is still getting crushed by homegrown competitor Mixi, with 12.7 million users. MySpace was second, with 1.2 million.
Hi5 has also benefited from rolling out its site in a variety of languages this year, doubling its audience to more than 56 million. Friendster, a social networking also-ran in the U.S., meanwhile boosted traffic 50% to 37 million worldwide.
Google's Orkut and AOL's Bebo also had strong gains--with 41% and 32% audience increases, respectively, in the last year. Neither has made big inroads in the U.S. market yet, however.