who's making a Diesel hybrid?
The French.
http://www.autoblog.com/2006/01/31/psa-peugeot-citroen-unveils-diesel-hybrid-technology/
There is a (needless) conflict between air pollution rules and fuel efficiency with hybrids.
Two problems:
1) US diesel has had significant sulfur (contributes to smog) for a long time because refineries didn't want to clean up to the standards that Europe has. That is now over and finally low-sulfur Diesel is coming to the US, years too late.
2) regulatory. The newest Diesels in Europe have a urea bottle which sprays a chemical to reduce pollution. The "problem" is that the current US smog regulations require that cars typically maintain their smog-lowering capabilities for 100k miles without maintenance, and having to put in more urea (maybe 30k miles?) automatically violates this.
This is just plain dumb, of course.
In Europe, the top of the lines, including BMW and Mercedes, are turbo-diesels.
Europeans don't value "neck-snapping acceleration" as much as apparently is so in US (though modern cars are all plenty quick enough), where Diesels are at a disadvantage versus spark ignition.
But they do deliver great "real-world" sensation of pickup because of the great torque.
Also people's notions of a proper size vehicle for ordinary use is totally skewed here. Trucks are for hauling cargo, not babies.