RE:China is coming to the table!!You really don`t under stand china housing market at all. Most of the empty apt that you are talking about are bought by the chinese diaspora around the world such as Singapore, HongKong, Taiwan, US, Canada and Australia etc... and these investments are done most in cash so even there is an increase in mortgage rate in the housing sector in China it won`t burst the bubble as in the western countrys. For the gold matter personally i think it will go higher because of the amount of paper money printed around the world and the huge amount of debt in the US would create a boom for gold.
Good investment and have fun