From a firefighter perspective there are always problems with technolgy, for example, I mentioned the Ethanol transportation problem, pipeline is the best, safest way, ethanol fires are very nasty, to the point that the current firefighting foams are essentially innefective.
ref:
Ethanol Fire Test Results
The hybrids have an extremely coorosive battery that, when the case is compromised, will react with the aluminum frame of the vehicle. I don't completely agree with tis article but here it is.
ref:
Hybrids and Emergency First Responders | Hybrid Cars
Lastly, propane and hydrogen cars have about the same hazards which is known as a BLEVE, this is when the container (compressed gas cylinder) is involved in a fire and ruptures.
ref:
BLEVE
which looks like this:
Pennsville Township Garage Fire with BLEVE
about the 6 minute mark there is a small propane cylinder explosion in a 2 car garage.
It's stuff like this that keeps me awake at night.