With the US dollar becoming more de-valued every day it will not take long for oil to double in cost. The production of that oil will cost more as well.
I will be surprised if it hits $5 a gallon by 2012 with out major events. But then again look what they pay a liter for gas in the UK and other parts of the world. Just some thing to think about.
They pay that much because the gov't there taxes the shit out of it, has nothing to do with the actual cost of the oil. You think the value of the dollar is going to half in a couple years? If that's the case, we have a lot more to worry about than gas prices.