A world currency??

Look... I know that there is no way that it would happen.
Heck, having a world currency would be as stupid as getting the government involved in our health care. Wait. What???

Here's the scoop:
Tim Geithner, your treasury secretary, and the guy in charge of socializing the bank and auto industry (slight sarcasm there), was speaking to the Council of Foreign Relations a few days ago.
According to Politico...

Geithner, at the Council on Foreign Relations, said the U.S. is "open" to a headline-grabbing proposal by the governor of the China's central bank, which was widely reported as being a call for a new global currency to replace the dollar, but which Geithner described as more modest and "evolutionary."

Read the article. I don't think that Geithner understood what the governor of China's bank meant. If that's true, its scary that our Treasury secretary didn't understand China's proposal:

The world economic crisis shows the "inherent vulnerabilities and systemic risks in the existing international monetary system," Gov. Zhou Xiaochuan said in an essay released Monday by the bank. He recommended creating a currency made up a basket of global currencies and controlled by the International Monetary Fund and said it would help "to achieve the objective of safeguarding global economic and financial stability."

Its completely understandable that the governor of China's Central bank wanted to take over all of the banks. That's China. That's the whole "Hey, how about if we all live under one ruler and have one currency" kind of thinking.
-And like I said, its scary, but possible, that Geithner, the same man who is spending us into oblivion with bailouts, misunderstood China's way of thinking and what the governor said.

But what made Geithner comment - out loud - about the governor of China's ideas without realizing that he is, you know, the Treasury Secretary?

I think it helps if you really think about what the Obama administration is about:
Celebrity.
Getting on television at every opportunity, no matter what the show. Sharing every single thought of yours, no matter how half-assed it is.

But you can't do that when you are the president. You can't do that when you are the Treasury Secretary of the US. Because people will taking your thoughts seriously, even if you don't.