In a country of over 1.3 billion people, undergoing rapid economic development (around 10% GDP growth per year), you would expect construction to occur at a rapid rate.
However, much of the new construction remains empty. Cities to house and employ over 1 million people have been constructed virtually overnight, but remain empty.
China's mixed economy is blamed. A limited degree of enterprise is permitted and much of this is oriented around construction. Regions also have minimum growth targets and the easiest way to meet these targets is simply to use government money to fuel construction. This construction is then sold off to investors, but the problem is that much of the population simply can't afford to purchase (or seemingly rent) the new properties.
The consequence is a polarisation between the emerging 'investor' class and the working class. (this is China we're talking about, so the word capitalist is a controversial one)
[YOUTUBE="http://www.youtube.com/watch?v=pbDeS_mXMnM&list=FLNUPHkbrEgqFW5lVXOlKerA& index=2"]China's Ghost cities[/YOUTUBE]
[YOUTUBE="http://www.youtube.com/watch?v=E9msCpYbyPs&feature=related"]China's Empty City[/YOUTUBE]