[nmh]

“Speculation has gathered speed over the last year, since the tumbling dollar has threatened to weaken China's buying power - and give it yet more reason to diversify into gold, oil and metals.”

Wrong “speculation”.

China sees the dollar spiraling DOWN.
The U.S. is a big determinant in the worldwide money supply. China's “buying power” isn't weakened. The Chinese do NOT see the U.S. dollar as a good investment. This is very bad news for the U.S. and worldwide currency.

[SwankyC]

China's “buying power” isn't weakened.

Well, since their currency is pegged to ours, it would be weakened.

[street_lawyer]

I do believe that China wants the Dollar to stay strong enough that we can afford their products. So China has been buying into our currency for that purpose. It's the last gasp of a dying U.S. Economy.