China has more than enough people, the challenge there is how to make them all consumers with fat wallets and raise their productivity.

They indeed import most of their energy and food stuffs. Like any big exporter, see Germany for instance. Really similar, just different consuming power.

For the housing bubble, it's part of planned development. It isn't as bad as a housing bubble in the US, as the government from China isn't democratic. The Chinese government can easily use its authority to tell the average Chinese to eat it up.