Peak oil has been a marginal theory for the past few years, either easily derided or simply too odd to mention. But this year's oil price spike has driven peak oil theory towards the mainstream. I'm seeing more instances in various journalism outlets. Even Paul Krugman gets peak oil.
Now, when the price rise stalls, then prices fall a bit, we should expect to see peak oil mocked as conspiracy theory, another instance of inaccurate doomsaying, etc.