Hubbert prestented his "Peak Oil" theory in the 70's and it's funny how every few months someone reads about it, allows paranoia to set in and prepares for the world as we know it to come to an end.
There is a lot of oil left in the world and we still have a lot of time to develope and refine techniques for the production alternative energy supplies. The only problem with our current oil supply is that the easy to extract and refine oil is running out. Most of the worlds remnaining reserve is oil that is harder and more expensive to reach and refine such as Canada's "oil sands" and the United States "oil shales". This oil costs a lot more to extract and requires complicated methods to refine into usable fuels. This along with fears propogated by the media and those who stand to benefit from it will continue to drive the price of oil to upwards.
The real problem for aviation is not the quanitity of oil left in the world but the cost of oil which will continue to drive the cost of flying up. How much the everyday joe is willing to pay to fly is yet to be determined. In my opinion aviation will be around for a long time to come but it may only be a luxury afforded only by the rich and big business.
We'll see which airlines will be left standing as the cost of doing business continues to increase. I bet we'll be around a lot longer than many of other airlines around the world. But really, who knows...