There's a huge difference between fuel cells for low energy devices like medical equipment and high demand applications like cars. One horsepower equals 746 watts. This is a physical constant and isn't subject to change or wishful thinking. A smallish car like the Toyota Prius uses over 100 horsepower, so you're talking about an energy demand on the order of 100 kilowatts. That's a lot of juice.

As to the cost of the GM project, that's a specious argument. Any handmade vehicle is going to cost a lot of money. The cost per kilowatt for fuel cells has been dropping over the years. Mass production can lower the costs even more.

Ethanol fuel cells are a good follow-on to hybrid electric technology. However, they require a catalyst to split the hydrogen from the ethanol, and that catalyst is still pretty expensive. It'll be a while before a pure hydrogen infrastructure will exist, but ultimately, that'll be a better solution than ethanol in the long term. Just as it takes a substancial amount of energy to produce pure hydrogen, it takes a substancial amount of energy to produce ethanol.