This week, the oil industry and Oil Patch watchers were all on the same side with their inventory guesses, but to vastly different degrees.

Investors often use energy ETFs as proxies for the energy markets, but how well do these funds really track their underlying commodities?

• The problem with futures-based funds
• Why you can't use USO and UNG as direct proxies
• Does the 12-month solution work?

Despite Fed Chairman Ben Bernanke's jawboning about the central bank's plans to sop up excess liquidity in the banking system, this week's market action isn't a likely catalyst for tightening. Declines in Treasury and commodity prices likely slipped the Fed's gearshift into neutral.

Forecasting changes in weekly oil inventories can be a dicey business. Sometimes the estimates made by the industry-supported American Petroleum Institute and sell-side analysts are widely disparate; sometimes they coincide. And sometimes, like this week, they can be on either side of the numbers posted by the U.S. Energy Department.

Traders held their collective breath this morning as they awaited a key U.S. Energy Department report on oil inventories. There were signs that the oil market was due for a bounce after selling off to pre-holiday levels amid concerns about trading curbs and demand slowdowns.

A small drawdown in crude oil inventories was accompanied by a much-larger-than-expected build in gasoline stocks, according to the latest government figures.

February crude oil hugged the $80 price level in overnight trading after a 2.1 percent sell-off in the Tuesday NYMEX day session, but prices sank further after a U.S. Energy Department report revealed a glut of petroleum products.

We often mention spreads in Desktop articles as trading alternatives to outright positions or as indicators of market trends. Because these spreads pit futures contracts against one another, however, many readers can't make use of them as investments.

One last sodden thought for 2009 ...