The New York Times today published an excellent op-ed: "'Peak Oil' Is a Waste of Energy":
"Let's take the rate-of-discovery argument first: it is a statement that reflects ignorance of industry terminology. When a new field is found, it is given a size estimate that indicates how much is thought to be recoverable at that point in time. But as years pass, the estimate is almost always revised upward, either because more pockets of oil are found in the field or because new technology makes it possible to extract oil that was previously unreachable. Yet because petroleum geologists don't report that additional recoverable oil as 'newly discovered,' the peak oil advocates tend to ignore it. In truth, the combination of new discoveries and revisions to size estimates of older fields has been keeping pace with production for many years."
~ Joseph Kellard