They'll doubtless continue to do well - that's a good thing - but they have plenty of issues of their own to deal with, including ethnic minorities, and a big democracy deficit that will likely become more irritating to a rising middle class.

I tend to agree with this. What matters to the "rising middle class" isn't so much democracy or not, but how much individual freedom and lifestyle they can have. Once the sustenance issue is solved, people want higher ends - more personal freedom, rights, information, opportunities, expression, etc. That being said, most Chinese are still poor and historically, it's been the peasant class that has caused the most problems for governments. It'll be interesting to see how the Chinese government balances the needs of the two groups.