Obviously, Twitter is the world's most famous micro-blog, but that doesn't mean that all micro-blogs are simply Twitter rip-offs. "Weibo" is the term generally used to describe all micro-blogs in China, a market in which no one player has the almost total domination that Twitter has in the West. What do you think?
For people who don't know what Sina Weibo is here is the wiki page http://en.wikipedia.org/wiki/Sina_Weibo