My, what amazing fear-mongering about natural gas. Are you paid by
the electric company, or what? Here's a different point of view, from
http://utilities.dteenergy.com/infoZone/safety/gasSafety.html:

The Facts

Natural gas is one of the safest energy sources available to
homeowners and businesses alike. By itself, natural gas will not
ignite. For ignition to occur, a mixture of gas between four and 14
percent must combine with air. Also, gas must have an ignition
source with a temperature of 1,100 degrees Fahrenheit or more before
it will ignite.

Because gas is lighter than air, it will rise and disperse. That's
why you should open windows and doors if you smell gas.

I suspect that if you research the subject, you will find that more
people are injured or killed and more property is damaged as a result
of electrical fires than as a result of gas leaks.

You mentioned, without any details, a gas main explosion which "burned
a whole community somewhere in California." If that really happened,
then sure, it's a terrible tragedy. But the fact that it happened
doesn't really prove much about the safety of natural gas, any more
than Boston's great molasses flood of 1919 proves anything about the
safety of molasses.