From HuffingtonPost.com:
Friday's Wall Street Journal editorial,  "Barack's Windfall Reversal," in barely contained gleeful  terms crowed that a transition spokesman "explained this week that  that the drop in oil prices to $50 barrel has made the windfall tax  a dead letter." The editorial goes on to point out with degree  of "I told you so" smugness, "left unexplained was why  the oil companies suddenly decided to stop profiteering, or manipulating  commodity prices."
Exactly the point. The oil companies  were not manipulating commodity prices. Their role was limited to cheering  on OPEC and lobbying our government to remain dangerously benign, playing  ostrich to OPEC's manipulation of the oil market.
 
You see, cartels are most effective in  rising markets where supply is relatively balanced or there is perceived  shortage of supply, thereby causing the cartel's manipulations to be  supportive toward ever-increasing prices. Discipline among cartel members  is readily maintained in that revenue from lower production is made  up from higher prices.
And as the oil hedge fund speculators  got blown away this year and as the world's need for oil began to recede  in the face of economic crisis, OPEC's control of the market began to  fade in classic cartel tradition. As supply moves from shortage to balance  and oversupply, control of the market begins to slip away from the cartel.  Revenues from reduced production can no longer be made up from higher  prices and the discipline of the cartel begins to collapse. The OPEC  cartel has no enforcement capability in place to police production quotas  of its members, and the propensity for cartel producers in analogous  situations has most always been to "cheat" around the edges.
 
More than anything, the march to $147/bbl  this year was in large measure due to the OPEC cartels success in manipulating  the supply of oil on the world market. Its success was tantamount to  a cartel imposed tax on consumers here and throughout the world. It  had nothing to do with the free functioning of the marketplace. At this  very moment OPEC is plotting to curtail production again at its scheduled  December meeting in the hope of changing the free market dynamics of  the market from current price softness (at the beginning of the Bush  presidency the price was closer to $20/bbl so even here "softness"  is relative) toward programming tighter supply and higher prices.