One of the big differences between Sina Weibo and Twitter in the west is that in China, many people who have nothing to do with the internet have become well-known because of Sina Weibo. Even if that person has absolutely no desire to become famous or well-known, or pursue fame.
This would be almost inconceivable in the west.
In many developing markets, this is how social media is really used. This was how the Arab Spring movement spread in 2011.