Diesel causes a bigger smog problem.
Bull, modern emessions equipment on diesel engines and lower sulfur content fuels result in more more pollution than standard gasoline engines.
The government needs to standardize the new deisel standards, so that things like TDI will be viable in the non commercial market.
All the mileage of a hybrid, and none of the nonsense! TDI is definately the way to go as far as I'm concerned... on larger commercial vehicles such as Buses the government is already funding working test cases of Deisel/Electric Motors for them (no no the battery nonsense liek the prius) but where the deisel is a turbine generating electricity which drives electric motors that turn the wheels... similar to what Deisel Locomotives, and large construction equipment have used for years... and it looks very promising.
Deisel as far as I can tell is a FAR FAR FAR more viable solution at the moment than hybrid.