Hydrogen fuel, you mean, for rockets? Definitely yes, for >50 years, and irreplaceable.
Oh, for other uses? That could prove to be one of the most expensive errors in human research, unless someone eventually finds a decent storage method (or until humans find an even more expensive error, of course). The progress of lithium batteries has made hydrogen less seducing in the last years.
I still see a future for hydrogen fuel: at aeroplanes
. Hydrogen's energy per mass unit improves the range and flight duration. Car fuel cells are already light enough for slower aeroplanes: helicopters far better than kerosene right now, 500km/h planes easy, 1000km/h planes not quite good. Design examples there with 100kg/100kW fuel cells, the last ones with up-to-date 50kg/100kW, including my tank design for liquid hydrogen.http://www.scienceforums.net/topic/75102-electric-helicopter/#entry748087http://www.scienceforums.net/topic/73798-quick-electric-machines/#entry738661