This is what I was getting at the Thursday Open Thread concerning the falling US Dollar.  

Some of the increase in the price of oil is due to the decrease in the value of the US dollar.  It is taking more dollars to buy the same unit of oil, but it's taking fewer euros to buy the same amount of oil.

I believe some of what is going on is the decreased holdings of US dollars at various national banks throughout the world.  What's replacing those reserves?  Gold, euros, and a basket of asian currencies?  You bet.  As I've heard it a millions of times...to understand the real driver of global activities....FOLLOW THE MONEY!!!!

The MSM (or the federal gov't.) do not want people to recognize this due to its ramifications.

And even though the IOB seems to have lost some steam, I keep feeling it's lurking under the noise.  Something is afoot here that is under the immediate radar.

Keep in mind that the us dollar has actually STRENGTHENED vs other currencies in the past 12 months, despite its recent slide. So viewed year over year, it take MORE euros to buy oil than dollars. Not disputing your general point but the slide of the dollar is still small and still very recent.
Menzie Chinn at Econbrowser has a nice pieceon central bank reserves and oil.  It includes this graph of global bank reserve increases lately:

Clearly, the oil exporters are becoming a growing part of the mix, with Asia becoming less important.  However, it's not at all clear that there's any relationship between the decision of what currency to use for trading oil and that of what currency to hold central bank reserves in (a point well made by Jim Hamilton back in January).

Since the Cdn dollar low in 2002, the US dollar is down 47.5%.