Below are two U.S. Dollar Index charts, one with the 10 year Treasury Yield.
U.S.Dollar Index (click to enlarge)

U.S.Dollar vs. 10 Year Treasury Yield

A look at the chart of Light Sweet Crude tells the story. As the United States' economy has slowed, expectations for global growth have been re-evaluated. Add to this the repricing of risk due to the over leveraging of financial institutions, caution has caused growth expectations to slow around the globe. That being said, looking at the price of Oil at $110, one would think that demand is sky high. It is not. Some commodities are now experiencing a disconnect from the forces of supple and demand. As the U.S. Dollar continues to weaken due to the lowering of rates and the flooding of liquidity by the Federal Reserve, as well as financing our excesses by debt, Oil and some other commodities have become a U.S. Dollar hedge. As oil and gas inventories come out here in the U.S., it is clear to see that the price of oil is not just a function of supply and demand any more. As the economy slows, and inventories build, the price of Oil should come down. This can not happen while the U.S. Dollar continues to fall.
This chart compares the price of Oil to the U.S. Dollar Index. At what point will the momentum of the Dollar's decline slow to the point to allow speculation in Oil as an ill advised hedge to be reduced? My calculations show that $111.25 is a price that could be a short term top, but that could easily be breached and prices running to $114.05 followed by $116.85. As long as the Fed is cutting rates, and becoming ever increasingly creative in bailing out financial institutions that should be left to swing in the wind, confidence in the dollar will continue to weaken.
Light Sweet Crude vs. U.S. Dollar Index

This chart shows that prices are firmly below the last triangle pattern. After the initial break below, there was one attempt back to the lower trend-line which failed. Since then prices went back down the second target price based on the opening range. It will be important to watch if the 400pt positive day for the DOW 30 can hold and act as support. Giving up this gain will be a sign of more weakness. Below is a monthly chart of the S&P 500 to give a longer term picture.
The U.S. Dollar use to be a safe haven when ever economic storms were on the horizon. With the inflating of every possible asset bubble over the past decade, the Federal Reserve has now decided to continue cutting rates when there is in fact little bubbles worth inflating.
The dollar should begin to strengthen when the Fed can not cut rates anymore and decides to focus on inflation. When oil goes from $110 back to $85, it will be seen as a new boom for the economy. Then the focus will be back onto which economy in the global market is growing the quickest, and has the most potential for growth.