Some bullish investors still regard the oil-futures market, showing sharply higher forward prices, as a stairway to heaven. To OPEC, though, which reduced its output quota by 2.2 million barrels a day Wednesday, it is a mountain to climb. The forward curve for Nymex crude prices currently slopes upward -- known as a "contango" -- and is extraordinarily steep. At $50.64 a barrel, the May 2009 contract commands more than a $10 premium to the "front month," or January contract. That spread has widened by about $7 in the past month. Farther out, futures rise above $70 from late 2012.