I can hazzard a guess to that one, it would seem that if the Fed is looking to stabilize their currency, they will need to buy back some of their dollars.

One of the reasons that they would like to push the value of the USD back up against other currencies is because they are worried that oil could start to be priced in Euros and not USD.

That would have even more repercussions for the US economy than the credit crunch. To do this they would need to buy their currency back in gold reserves, which would flood the market and devalue the price of gold.

just my thought on that subject