An anonymous reader writes "China's 450 million Internet users have taken to social networks in a big way. But these social networking sites, founded on the promise of free expression, have an uneasy existence under an authoritarian regime that punishes certain kinds of expression. This article from IEEE Spectrum tells the story of Sina Weibo, the white-hot social networking phenomenon that has taken over China in the past few years. Citizens have used the microblogging service to protest and rebel — but the Chinese government is getting more sophisticated in its handling of these online grumblings. Side note: an English-language version of Sina Weibo is reportedly on the way. Wonder if it will take off in the US?"