At least three miracles are needed for hydrogen vehicles to become practical and progress has been made on two of them this week.
1) cheap way to produce the hydrogen.
2) practical way to store the hydrogen in a car.
3) cheap fuel cell to use the hydrogen - progress is coming along generally. this is probably the easiest miracle, but it is at the product development stage so companies don't talk about their progress.
We obvious still need to get the energy to produce the hydrogen from somewhere and I think the crazy unschedule-able wind plants will do just fine for that. The hydrogen production facilities will only be profitable with the lowest cost electricity. The electric companies will give them the lowest rates in exchange for the hydrogen companies agreeing to follow the wind plants' output.