Ted B. wrote:

A number of reasons, the main one being that gas (only) designs have been
refined over many years to the point where even the worst of the bunch are
pretty darned reliable. Diesel (only) designs are pretty close, in terms of
reliability, but not QUITE up to par with the gas (only) vehicles yet.
Again, there are exceptions, but if you want to play the odds on a car that
will last a long time, gas (only) is your best bet right now and Japanese
makes are also your best bet.

A lot of people do not understand the reliability issue with hybrids,
since they are so new. Similarly, many people believe that since diesel
engines are so reliable on trucks, that the same extends to cars, but
this hasn't been the case in the few diesel passenger vehicles sold in
the U.S.. Actually there are some very reliable automobile diesel
engines from Europe and Asia, but most don't make it to the U.S. because
of the sulfer content in the diesel fuel. Onc we have the same low
sulfer diesel fuel in the U.S., it will make diesel engines in cars more
practical.

All things considered, gas (only) is the best bet, right now (2005). -Dave

Probably for several more years as well.