Oil is a electronically traded commodity now, afaik. There is no master plan being devised, it is greed, pure greed of traders.
When I take my Chrysler van to get gas, I try not to look at the price sign, although it is pretty good on gas for the size. The Prius, it doesn't impact me so much, as I use 7-8 gals to go 400 miles. Wifes MB, using premium only, low mpg city driving, it is a sinking feeling going to the station now. $4 is near on prem.