Jet Blue is in trouble these days, losing money and too many planes coming in that they have nowhere to put.
Expect them to defer deliveries soon. The legacy carriers have cut back their expenses like crazy, and most of them are on track to do quite well this year, at the expense of Jet Blue and Southwest.
JetBlue mis-calculated on Fuel Costs. They do have places to put the bigger planes. A real problem for them is that they abandoned (to a small extent) their original business model of flying one, and only one, plane. They are adding a smaller jet. This will cost them and was a dumb move. Unlike the dino airlines, JetBlue's problems are not being caused by a lack of customers. Regardless, I would fly them over the dinosaurs anyday.