Most of the short term projections for fuel cells assume that hydrogen will come from existing natural gas wells, where electrolyzers aren't used. But for a long term renewable energy system hydrogen will have to be generated from electricity or biogas. Then electrolyzer and fuel cell efficiencies will become important. In this one area of efficiency it looks like batteries still have an advantage. But the true believers at the conference were having none of this.
Fuel cells are the future and there is no question about it in their mind.
Personally I would like to see the efficiencies of zinc-air fuel cells, flywheels, advanced batteries, and other energy storage systems before I put my vote on fuel cells as the future of energy.