Tencent’s QQ instant-messaging platform used to be the darling of China’s marketing community, but with astonishing speed – even by Chinese standards – Sina Corp.’s microblogging service Sina Weibo is the new front-runner. Often referred to as China’s Twitter, the two-year-old microblog has taken off among celebrities, executives, politicians and, unsurprisingly, advertisers. Sina Weibo, launched by one of China’s leading portal sites in August 2009, has dramatically altered that country’s digital behavior, pulling users’ time and attention away from other websites such as QQ, video-sharing platforms Tudou and Youku and, most of all, Facebook clones such as RenRen and Kaixin001. (Twitter is banned in China).