Jim Chanos is short China. As with many big events, the circumstances have an overabundance of murk.

CN's gov't has a legitimacy problem due to its corruption ( see CorruptionByDesign ). Many Party criminals have made a lot of money during this development boom via extortion / appropriation, so an economic crash could result in large-scale political instability.

To prevent that, we'll probably see a drop in CN's foreign currency reserves as the Party tries to bail out the economy (or less charitably, its friends). However, CN doesn't report currency reserves to the IMF, so this could be happening right now...

Additionally, I would put very large error bars on any statistics coming out of China, especially development numbers since local Party rewards derive partly (mostly?) from construction.

That said, CN is industrializing and has to build city for millions of farmers. From Chanos' numbers,
2.3B m^2 office space =~ 25B sq ft =~ 25K * 1M feet^2 skyscrapers.

With 160 cities with more than 1M people, that's roughly 160 skyscrapers per city. That doesn't seem inordinate, especially if a bunch of old buildings were plowed down to make room for them.

So we have something that may be a problem, the gov't has a vested interest in fighting problems, and we have little visibility into the economy. In this inky dark, it seems our best guiding lights will be inflation and rent prices.

As long as they keep increasing, then the party's probably not over yet. ;)