Good article in Red Herring last week on the debate over when fuel cells are going to be commercialized. As the article notes, micro fuel cells for battery replacement are likely to be the first to be commercialized, but challenges remain.
Also note the entertaining quote from an ABI Research analyst:
"People have been saying for years, ‘Next year is going to be the year.’ But maybe this year we really can say that next year will be the year that we’ll be seeing some of these."