Julian D. W. Phillips maintains that central banks are beginning to restock their reserves of gold.
Private hoards of the yellow metal are beginning to rival national ones: the world's largest gold ETF, SPDR, is well into the top 10 - Bloomberg reports it's now overtaken Switzerland. But there is some question of how much of SPDR's holdings are actual physical gold.
Gold doesn't earn interest, which is one reason why China hasn't yet (apparently) leapt in, though Commodity Online says that country has been considering it.
Some say that the Chinese government likes to declare policy changes via apparently unofficial sources. It's worth noting that the China Gold Association called last November for an expansion of national holdings of gold beyond its present level of 600 tonnes.
China's recent switch from Agencies (local and State bonds) to Treasuries, and from long-dated Treasuries to short-dated ones, seem to indicate contingency planning for a worst-case scenario in which the US loses control of its budget and money supply.
The motivation to plan for the worst, is high. China's official holding of US debt, large as it is, is understated, according to Brad Setser, who believes that much of the investment in US Treasuries by the UK and Hong Kong are actually on behalf of China.
In the same way, I can imagine that China might wish to hedge its bets on America by quietly boosting its gold purchases, using intermediaries to take positions in large gold investment funds. This would be a typically quiet and indirect way to improve its own security without making open moves that could panic the market. And the funding for these purchases might come from selling US/UK government bonds back to us, thanks to "quantitative easing".
What's sauce for the goose, is sauce for the gander.