By Sui-Lee Wee
BEIJING (Reuters) - Living in one of the world's most heavily censored societies, Wang Yong enjoys anonymously venting his daily frustrations, 140 characters at a time, via China's version of Twitter, but new government restrictions are making him think twice.
As of Friday, Beijing-based microbloggers were required to register on the Weibo platform using their real identities or face unspecified legal consequences, in a bid to curb what Communist officials call rumors, vulgarities and pornography.
Many users, however, say the restrictions are clearly aimed at muzzling the often scathing, raucous - and perhaps most significantly, anonymous - online chatter in a country where the Internet offers a rare opportunity for open discussion.
"Definitely, I will not use Weibo if they need real names," said Wang, a 27-year-old government employee who said he loved being able to post his thoughts anonymously. "I don't want to be supervised because of my words."
Weibo, which means microblog in Chinese, is operated by several companies, the biggest of which is Sina.
Despite Premier Wen Jiabao's calls for greater political reforms, the ruling Communist Party has shown little sign of loosening its grip on power, or allowing public dissent.
Wen, who is due to hand over power next year, told his last news conference at China's annual parliamentary session that letting off steam via the Internet was "normal".
But as no other public forum offers people the same freedom of debate that microblogs do, operators deploy a host of measures to monitor content, blocking and removing comment deemed unacceptable, especially posts with a political slant.
Even with all the censorship, Weibo users are able to access vast amounts of information that they would never have been able to some three years ago, as Facebook, Twitter, Google Plus and other similar services are blocked.
It is unclear how strictly the authorities will enforce the identification rules, which may also be introduced in other major cities such as Shanghai and Guangzhou.
By midday on Friday, only 19 million out of more than 300 million users of Sina had registered their identities, and several microbloggers told Reuters they would not sign up.
"I'm sure I will not use it any longer," said Sheng Hui, a 28-year-old employee at a foreign bank. "Weibo, for me, is just a tool to blow off my anger and pressure. I won't be able to shout abuse in future."
Part of the appeal of microblogs stems from the failure of the state-run media, said He Weifang, a law professor at Peking University and a regular microblogger, who, like Premier Wen, understands the platforms' "safety valve" value.
"China's official media has done a very poor job of reporting criticisms of the government and exposing society's weaknesses, so a country like ours needs to rely on the informal media," He said. "Once the people can express their opinions online, they don't have to take to the streets."
On Thursday, one of the most talked about issues on Sina's microblogs was Bo Xilai, the ambitious Communist Party leadership contender who was sacked from his post as head of the inland city of Chongqing.
Zhang Ming, a politics professor at Beijing's Renmin University and a frequent microblogger, said the new rules were aimed to "limit microbloggers' ability to expose malpractice by the local governments and bring whistleblowers immediately under control".
(Additional reporting by Sabrina Mao and Beijing Newsroom; Editing by Ken Wills and Miral Fahmy)