Hydrogen parade proceeds (but where are the plug-ins?)

For those of you who missed it, there's a parade of hydrogen-powered vehicles moving across the United States to publicize this form of alternative energy.

Here's the account by the Globe's Erin Ailworth of the stop last week northwest of Boston in Billerica, US HQ for hydrogen fuel cell maker Nuvera and home of the PowerTap, the state's first hydrogen refueling station. Here are pictures of the fleet.

The excellent green blog Grist caught up with the tour in Washington and notes that if you live is Smyrna, Tenn., tomorrow is your lucky day to see the parade. Comments on the Grist post note the conflicts in hydrogen (two questions posed: 1) Why wait on a new technology when we can be moving/grooving on plug-in hybrids? 2) Won't these things just run on gas as a conduit?)