Well, the streets of California at least. The company had previously released plans to have a hydrogen fuel-cell vehicle on the road by 2015, but that schedule has been bumped up a year to meet the incentives within California's Zero Emissions Vehicle mandate.
“So much of what happens is directly related to the California ZEV mandates — they’re followed by at least 14 states, and they affect nearly half of the cars on the market in the United States. Phase IV of the mandates covers model years 2015 through 2017, so that means we could begin complying in late 2014," John Hanson, a Toyota spokesperson, told the New York Times.
California's ZEV scheme has previously influenced Toyota and other carmakers, including General Motors, to introduce zero-emissions vehicles, including the RAV-4 EV and the much-discussed EV-1.
This time around, the monetary benefits to California's program are such that it's now a valid business case for Toyota to build the hydrogen fuel-cell car.