The Internet is justly said to be the freest space available for self expression in China.
Though China is home to nearly 300 million Internauts, more than anywhere else, "the country's Internet environment remains one of the most controlled in the world," says the report by Freedom House, a New York-based human rights group.
Blocking foreign websites is a common tactic: YouTube has been inaccessible for most of the past week, since Tibetan exiles posted a film showing Chinese militarized policemen savagely beating Tibetan monks and civilians. The video-sharing site has been blocked before.
The government also jails citizens who use the Internet for unapproved purposes: Last Saturday Tan Zuoren, who was compiling an Internet list of child victims of last year's Sichuan earthquake, was arrested and charged with "subversion of state policies," according to the Center for Human Rights and Democracy.
Still, netizens are constantly finding ways around censorship, pushing the envelope on what is tolerated, and making the Internet "a primary source of news and a forum for discussion for many Chinese," the Freedom House report says.
"Netizens' energy is always there," says Xiao Qiang, editor of China Digital Times, which monitors the Chinese web. "It's like a river; you can block it in one place and it flows somewhere else." [Editor's note: The original version misidentified Professor Xiao.]
The Chinese web presents a paradox, adds Rebecca Mackinnon, a web expert at Hong Kong University. "You can point to examples of how speech is getting freer on the Internet and to examples of how it is tightening, simultaneously," she says.
Ordinary citizens, Ms. Mackinnon suggests, are delighted by the surge of information that they can now find on the web, and by the unprecedented space for general discussion of public issues.
More politically minded Internauts, on the other hand, are "very frustrated" by the number of blog and forum posts that never make it onto the web or that get taken down by website administrators.
"Right now all websites are under extraordinary pressure to control themselves" to avoid inflaming passions at a time of economic downturn, with the approach of sensitive anniversaries such as the Tiananmen Square massacre on June 4, 1989, the nation's founding in 1949, and others, says Professor Xiao.
"The controls are coming down again harder than at any time before," he adds, "because they are not aiming at information but at getting web companies under control."
"Killing the chicken to scare the monkey," as the Chinese proverb has it, the government has recently closed down more than 3,000 websites on the grounds that they published lewd content. The crackdown, however, also closed a number of discussion forums where commentators had been unusually daring.
Website administrators trying to avoid that fate are thus well advised to abide by the "guidance" that Internet supervision officials send them periodically, warning them off certain subjects.
Last month, for example, all major Chinese news websites were ordered not to post anything to do with an expected environmental impact report on a massive oil refinery project in the southern city of Guangzhou. The official internal notice, leaked and widely published on blogs, forbade sites to publish even the report itself, which is meant to be public and open for comment.
This week the State Administration for Radio, Film and Television announced that no site can post foreign films or television programs – which are very popular here – without special permission.
"This is different from the past," says Xiao. "They want to proactively keep the Internet under control. It's a pretty thorough and systematic campaign."