Users in China are reporting that access to LinkedIn has been blocked throughout the country. By all indications, it seems that the popular career networking site has run afoul of the country's infamous Great Firewall .
According to LinkedIn's Hani Durzy, the company is aware of a blockage in China and is "currently in the process of investigating the situation further."
The shutdown follows days of calls for a "Jasmine Revolution" in China , on the model of the Tunisian and Egyptian revolutions. Access to Twitter and Facebook has been blocked throughout China for some time; Chinese internet users seeking to use Twitter have been forced to access the site through difficult-to-use Virtual Private Networks (VPNs).
However, Chinese dissidents have another way of accessing Twitter...LinkedIn.
Use of LinkedIn, which is fully integrated with Twitter, was by far the easiest way to access Twitter in China. Messages can be easily read and posted through Twitter via LinkedIn.
One Chinese Twitter user who accesses both Twitter and LinkedIn through a proxy posted photos to Twitpic  that seem to confirm a Chinese LinkedIn outage.
Adding credence to the LinkedIn-shutdown-to-block-Twitter strategy is the news that the Chinese government has started censoring the name of U.S. Ambassador Jon Huntsman  from search results on the wildly popular homegrown Twitter/Tumblr clones Sina Weibo/QQ Weibo. Weibo means “microblog” in Chinese.
Huntsman faces widespread charges in China of support for the Jasmine Revolution after a citizen journalist spotted him watching a pro-democracy protest  from within a crowd this past Sunday. Like any good American abroad, Huntsman was standing outside a McDonald's.
According to The Wall Street Journal, Chinese dissidents have been disseminating calls to protest and organizing events  via LinkedIn.
Reuters notes that the LinkedIn outage could hurt the firm's chances at an IPO :
If the disruption for LinkedIn is permanent in China, it could hurt the company's prospects at an IPO as a ban would exclude the company from the world's largest Internet market--about 450 million users and growing.
"It certainly would be a negative in terms of the company's future growth and profitability," said Jay Ritter, a professor of finance at the University of Florida.
"This is something where investors would take it into account and be willing to pay a little lower price per share."
Luckily for LinkedIn, China's Internet censors are notoriously fickle: Sites blip on and off the Great Firewall frequently, with no prior warning.