It matters if you like clean skies and believe that global warming is, indeed, a threat. If you don't, go ahead and go back into the Dubya Tent. Fact is, most automakers agree: hydrogen fuel cell vehicles are a serious and needed part of future mobility solutions. Honda's FCX seems to be the most advanced fuel cell vehicle today, and while it's a concept, the good news is that it will be on sale as early as 2008, thanks to significant advancements in making the cell smaller, stretching vehicle range to 270 miles, and improving power – the concept can get up to at least 90 mph.