Demand for gasoline in the US has actually declined about 1% over last year's rate (Lundberg Letter?). Global demand however, has continued to rise. Csaba Csere in Car & Driver magazine has an excellent article illustrating the pickle that we are in regarding fuel prices, look for the issue with the 08' Challenger on the cover.
On the brighter side, once the rest of the world realizes that the myriad of bundled subprime mortgage investments we've been unloading on them are worthless, global demand will indeed decline as they begin to realize that they aren't so wealthy either . By that time, our dollar could be on par with the peso though.
