Or I could upgrade from oil to gas for $14K (to an 82% efficiency boiler). I have a strong incentive to do this since the cost of heating with gas will be 1/3.5 compared with heating with oil.
I think these are insane prices, but that's what contractors get around here. There is a $10K incentive for the heat pumps, but it requires a home inspection and probable upgrade of the insulation. IMHO, the incentive is not enough- it needs to make the heat pumps the cheapest option.
As far as fuel costs, the gas would definitely be cheaper. The electricity comes from gas (especially in the middle of the winter). The price is more because you are paying someone to convert the gas to electricity. The efficiency of getting the heat from gas via electricity is only a little more with heat pumps (when accounting for generation and transmission loss and much higher heat pump efficiency).
Maybe in the future the electric supply will be greener, but it isn't today. They are trying to build a HVDC line from Boston to Quebec for more hydropower, but Maine and NH are not allowing it due to NIMBY (a referendum in Maine, financed by gas companies, killed it).