Sina Corp is a Chinese new media company which operates the 3rd largest by traffic website in China, microblogging site Weibo.

Bloomberg published a story on 3/21 beginning:

Sina Corp., China’s third-most visited website, led gains among the nation’s Internet companies after Google Inc. (GOOG) said the Chinese government is blocking its Gmail e-mail service.

Without really explaining a connection between the stock's rise that day and the Gmail development, the writer undercut the Gmail argument as follows:

“Sina is a market leader in microblogging service in China, where fast growth has been a hot topic in the past few months,” said Chunming Zhao, an analyst at Susquehanna Financial Group LLP in Boston. “I don’t see a very direct relationship between its gains with the Gmail service problems in China. The rises in the broad Nasdaq index helped with Sina’s increases.”

Sina is preparing to spin off its microblog unit and is in talks with investment banks for an initial public offering, China’s 21st Century Business Herald reported March 8.

So really it is just a hot stock - but the issues with Gmail drive the point home that China's tight control over its media mean that Twitter and Facebook are by and large global brands - lots of people in other countries use those sites even though they are American. 

But the Chinese are protectionist and it will be sites like Weibo which will captivate the largest internet market in the world (457 million web users).  Thanks to Google Chrome translation, I was able to get some feel for what the site is like, and I wanted to share this with you:

 jinn Tony : Although not very valuable, but still a good few months to accompany me to mourn my poor little phone I'm sorry - - do not take good care of you ... Fortunately, this did not insist the little gray rabbit home, I is not good, I failed. . As for the thief, I wish you good luck!

So I don't know what you take away from that, maybe Google translate is not perfect, but it's pretty cool :)   I am not sure if now is a great entry point to Sina, but I could see it rising quickly.