the data used is not based on IPs, but on user-submitted "current cities" instead, as mentioned in the blog post

Oh, huh. That's weird.

I wonder if Chinese Internet users for some reason think they'd be caught evading the filter if they put their actual city in their profile?

Or maybe his sampling method was just abysmal? ;)

Or maybe Chinese people just don't use Facebook.

Yes, I made that post before I saw what smokinn said about QQ. (And what others said about other Chinese social networking companies, and American companies in China, in general.)