From CNN:
A handful of homegrown micro-blogging sites emerged about the same time Twitter started to gain a small, yet steadily growing, share of Chinese Internet users, beginning about 2007, around a year after Twitter was launched in the U.S. in 2006.
While almost all of the early Chinese micro-blogging pioneers faced the same fate as Twitter, most of the sites are now back online and are fiercely competing to gain a share of what many predict will soon be an exploding population of Chinese micro-bloggers.
Alex Mou is the founder of one of them. He started a Twitter-like site called Zuosa, which was shut down for “self maintenance” on July 21, around two months after Twitter was first blocked in early June.