Good article, I work in the natural gas industry very close to the Haynsville Shale. Natural Gas refueling would require a big investment in infrastructure, probably a mandate by government to build refueling stations. Since I don’t like mandates from the government and believe that prices will dictate changes we will just have to wait. To much oil in the ground yet but America has more Natural Gas than it realizes. Potential is there.
It is a growing market, but has a ways to go.
Natural Gas Fueling Station Locations
http://www.afdc.energy.gov/afdc/fuels/natural_gas_locations.html