Has to be James Fallows. As much as I believe you have to be able to speak Mandarin to get a good grip on China, he seems to have managed without total fluency. His article on the trade deficit was probably one of the best things I've read on China in the past year, and given the volume of Sinopunditry we've seen in this Olympic year (a lot of it pretty awful and cliche-ridden, it has to be admitted), that's saying something - not much, but something. He's also a prolific writer and answerer of letters and emails, something which is worth a lot in my book.
A mention also must be made of Steve Dickinson, he doesn't write as much for China Law Blog as he might, but what he does write is always good. His piece on China's new anti-monopoly law was particularly good.