I think technology solves those issues of hazard (Hydride Storage) and expense. (20 years ago I bought a PC for $4000, now they're $300.)
The automotive industry leaders like Honda are already deploying Hydrogen Fuel Cell Vehicles in California. They are leasing them for $600 per month to folks who live near their filling stations.
http://automobiles.honda.com/fcx-clarity/?from=fcx.honda.comThat's not PR.
That's an admission that Greenhouse Gas Regulations - and they are coming - will require infrastructure changes in the transportation field.
Battery development may exceed Hydrogen Infrastructure. Hydrogen FCVs are simply a oxidative fuel fed battery which produces DC Electrical Power.
The industry considers BOTH technologies viable at this point.
There were no petroleum pipelines in operation when Henry Ford started building gasoline powered cars. The idea necessitated the development.
(There was no internet when Bill Gates first built an operating system for a PC... same deal)
Even without Greenhouse Gas emission concerns - Exxon, BP, Royal Dutch, and Chevron won't always be oil companies, according to Hubbert's Peak Theory. They'll go where the money is.
Hubbert's Peak Theory suggests that as oil usage exceeds oil deposit discovery, prices will rise rather sharply. This economic pressure will drive diversification into other energy sources.
Science tries to play nice and suggest alternatives.
Economics plays hardball and requires it.