I'm not a petroleum geologist (one of the myriad things I'm not), so I'm not equipped to evaluate either the method or the conclusion (aside: Deffeyes himself puts Hubbard's Peak for world oil production:
see http://www.princeton.edu/hubbert/current-events-01-16-04.html)
I don't know of any direct critiques. It occurs to me that one could only apply the extraction curve of an oil field to total petroleum reserves only if the extent of total petroleum reserves are known, but perhaps there's a drop off in succesful petroleum prospecting?
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The topic of peak oil generates a lot of confusion with some folks dismissing it as a simple, malthusian 'end of oil' hypothesis and others accepting the theory as sound and confirmed (to the extent a non-specialist can).
It's always useful however to seperate an original idea (of anything) from what that idea spawned as time goes by.
Consider, for example, this excerpt from the Wikipedia description of Hubert's work:
Hubbert made use of a mathematical model of the rate of petroleum extraction. According to this model, the rate of production of oil is determined by the rate of new oil well discovery; a "Hubbert peak" in the oil extraction rate was forecast to be followed by a gradual decline of oil production to nothing. This behavior has the form of a Hubbert curve; see that article for mathematical details.
Based on his model, Hubbert forecasted (accurately) that, following from the peak of well discovery in 1948, oil production in the contiguous United States would peak in the late 1960s based on a total production of 150 billion barrels or in the early 1970s based on a total production of 200 billion barrels. It actually peaked in 1970, and has been decreasing since then. According to this model, complete exhaustion of continental U.S. oil reserves would then follow by the end of the 21st century. While the Hubbert model has been very accurate for forecasting oil production in the contiguous United States, it has fit much less well the production curves in other areas.
full at - http://en.wikipedia.org/wiki/Hubbert_peak
. . . . . . . .
Now the theory this Wiki author describes is rather modest - focused on the specific prospects for U.S. domestic oil production. The more broadly targeted theory now known as 'peak oil', which claims the world as its model, is less successful - to date.
So here's where the confusion apparently lies - as the Wiki author crisply describes, it works very well for predicting the North American situation because we have a solid idea of where the reserves are and how much crude remains. But it runs into trouble when applied to the planet as a whole because we can't be certain we've found all the major petroleum reserve sites.
.d.