Even as they compete for market share, Sina’s Weibo and Tencent’s Weixin have evolved to fill very distinct user niches. Last week, amid the high-profile trial of disgraced politician Bo Xilai, the differences between China’s top two social-media services were clearly on display.

The Jinan Intermediate People’s Court took the unprecedented step of broadcasting select bits of the proceedings against Bo in real-time over Weibo, China’s Twitter-like microblogging platform. Observers hotly debate whether the court’s messages published during the trial demonstrated increased openness or simply more sophisticated media control. Chinese celebrities, meanwhile, turned to Weibo to share their opinions on the trial, too. The service has amassed 500 million registered users since its launch in 2009 and has become a popular forum for airing grievances and tuning into public figures’ remarks on the news — subject, of course, to nearly real-time government censorship.

Weixin, which was launched in January 2011 and quickly amassed about 400 million registered users, is used with more intimacy to share text, images and short voice messages. It’s akin to Facebook, but not quite the same as the giant social network from Silicon Valley. A person’s posts are visible only to “accepted” friends, and the kinds of information shared — photos of one’s children or random observations about the day — are typically intended only for a defined circle of friends and family. Publicly “tagging” friends in photos and posts — one of Facebook’s signature functions — doesn’t exist in Weixin; instead, what appears on your timeline is entirely controlled by you. Unlike Weibo, it’s used almost exclusively on Internet-enabled mobile devices, not desktops.

The speed at which Weixin has been integrated into daily life in urban China is striking. At a wedding this July in Zhangjiakou, a midsize city in northern Hebei province, guests waved smartphones to take photos of the bride and groom — and several photos appeared on Weixin before the ceremony was even over. During a visit to factories in southern Guangdong province in August, several plant managers extolled the virtues of handling direct customer service via Weixin.

To tap the pulse of public sentiment on the news in China, check out Weibo. But Weixin may have a brighter future for viral marketing and professional networking. It also has global ambitions, with about 100 million registered users outside China and an English-language version called WeChat. As of August, as the tech website reported, Weixin was also the fifth most popular smartphone app.

Via Mashable