This is probably somewhat obvious, but I suddenly stumbled across the thought that a belief in forthcoming catastrophe resulting from running low on oil is pretty much impossible. There are a lot more worries about the economy today with oil bouncing around $50 than there were when it was $100, before the financial problems really started hitting home. Similiarly, the world has proven that it can take $130 oil without too much discomfort. I find it very hard to believe that renewable sources are more expensive than that.
Not saying such a transition would be cheap, it would likely render several large vintages of capital equipment obsolete, but predicting a peak oil crisis just seems foolish to me now.