This would replace the US dollar as a reserve currency.

It would obviously weaken the US dollar in the long run, which is not necessarily a bad thing, the “strong dollar” policy of Robert Rubin (and Larry Summers, and Timothy Geithner, and Ben Bernanke) benefits Wall Street at the expense of main street, and is long term unsustainable.

It is unclear to me as to whether this is a real move for change, or simply an attempt by China to assert itself on the world economic stage, though.