There is an article today noting that diesel models offered to the public are expected to double in 2014. Europe has been a fan of diesel for many decades now, but the US has been averse.
There is now some great competition setting up, if one can believe the media. We have the perennial gasoline engine which has been seeing a big renaissance due to direct injection and cleanliness and boosted mpg ratings. We have a push for nat gas engines as we seem to have an abundance of nat gas for the time being. We have the hybrids which have shown huge increases in mileage despite a small penalty in cost and complexity. We have the surge of all electrics which seem to be a surprising study in efficiency and increasing battery range and life. And we have the fuel cell which has some vehicles on the road in testing but still suffer from an infrastructure problm the others have less of an issue with.
Automakers are making a big bet on keeping the gasoline and hybridizing the gasoline. Electrics are a real surprise and many new electrics are coming in the next couple years. Diesels...well I don't see a long term future for the passenger car market at least in the US nor do I hold much hope for nat gas passenger cars. Fuel cells are still a promise, but seem to be always pushed out another 5 years every 5 years.