And they absolutely lost their shirt on flying them.
150 a barrel oil is coming as it gets harder and harder to find.(BP wasn't drilling in water over a mile deep because its cheap or easy...its because it's getting harder to find oil to meet even todays current demands) The effects on anything that uses oil (such as transportation) will be profound and forever.
We may very well see turboprops make a comeback as they may be the only aircraft that can make money on short, thin markets.