Saudi Arabia is predicting that world oil reserves will continue to increase in coming years, discrediting the theory that "peak oil" production has already been reached. The CEO of Aramco estimates enough oil for more 140 years at current production levels. After that time, we better have developed practical solar, wind, ocean, fusion, or fission power sources.
UPDATE: A University of Washington economic geologist, Eric Cheney, claims that there is lots of oil left.
UPDATE II: Cambridge Energy Research Associates, Inc. also disputes the peak oil theory.