Diesel has been cheaper than gas for me for quite some time now.
Break even cost in the car itself is what I'm referring to. A 328i vs 328d is only $1500 brand new. It's a very short break even life. Probably a year or less in fuel and mileage savings.
At that, when I was car shopping used the only diesels they had CPO were 10k over the 320i with the similar options and similar miles. The car we bought ended up being significantly cheaper and I wouldn't have broken even for a long long time, if ever. At that, when fuel prices are lower, including diesel, the break even point gets much further away. Then once you factor in the residual value at trade in, it was a no brainer, 38-40 mpg on the freeway was plenty good. In stop and go traffic, the whole 15 mile commute to and from work, it's hitting 28 mpg. Weekends, its around 37 combined which isn't awful. But it has less power.
And ya'll are paying higher prices for a change than us. I paid 2.09 to fill out the 320i with 91 last saturday.