Weibo is also going official. Thousands of government agencies and officials have weibo accounts.
Jin Zhongyi, director of the Haining Justice Bureau in Zhejiang Province, opened his weibo account in October 2009. "It's fast and transparent, but more importantly it allows us to interact with the public, supervisors and experts."
He has asked all departments in the bureau to set up an official weibo account and encourages his colleagues to use weibo. "I believe it's the only way we can truly hear the voice of the people," he said.
Social activist Wu isn't so sanguine. He said his weibo has been shut down at least twice by someone in authority who didn't approve of what he was writing. "A weibo is just a place where people can express themselves, it doesn't mean we can speak randomly."
Professor Hu believes that for a very long time, weibo or any sort of social networking sites in China will not become the tools for revolution. "It's more like a facilitator of transformation," he said.
Others believe that despite supervision, microblogging is the most open platform for expression available in China. "It's breaking taboos," said reporter Deng, who is organizing a charity campaign on his weibo to provide free lunches for poor children in western China. "When there are many people discussing sensitive issues, they're no longer taboo."
Both weibo and Twitter have a 140-character limit. But Sina weibo (left) allows users to post pictures, videos and audio directly and to even start a vote; while Twitter (right) is text only.
Who's following who
Tencent (all numbers updated as of 5 pm Wednesday)
1 Liu Xiang (athlete) 16,018,982
2 Ma Yili (mainland actress) 15,809,472
3 Karen Mok (Hong Kong singer) 15,800,570
4 Kai-Fu Lee (former chief of Google China) 15,445,111
5 Kevin Tsai (writer, Taiwan TV show host) 15,269,866
1 Yao Chen (actress) 8,181,620
2 Hsu Hsi Ti (Taiwan TV show host) 7,313,605
3 Kevin Tsai (writer, Taiwan TV show host) 6,651,791
4. Zhao Wei (actress) 6,475,431
5. He Jiong (TV show host) 5,998,381
1 Lady Gaga 10,126,188
2 Justin Bieber 9,708,306
3 Barack Obama 8,063,640
4 Britney Spears 7,868,485
5 Kim kardashian 7,505,308