Put me in the optimist camp also. We always forget our ability to adjust to changes in price. Now we can't do much in the short term... we will still be stuck with our GM Suburbans for the next few years. However, at $100 dollars per fill up, many will still switching over to more efficient forms of transportation and our comsumption will level out. At the same time, other sources of energy (solar, oil from sand in Canada, mining of the moon etc) that were not previously economical with oil at $25, will be very profittable at $70. I really think this is a short term spike and $50 guestimate may not be that off.