As for transport, that's what a power grid is for. Transporting hydrogen loses more efficiency than transmission losses.
Batteries are way ahead on every objective measure, and getting better every year.
See the Hydro section of Sustainable Energy - without the hot air by David JC MacKay:
http://www.withouthotair.com/c8/page_55.shtml
Even though the land mass of the US is larger than the UK, it's hard to see hydro being more than MacKay's 2kW per day per person...
That's two 40W light bulbs left on all day.
The goal of pumped storage isn't to create new electricity, but to store large amounts of unused baseload power. This can be done with a standard hydroelectric dam by pumping the water back up into the lake behind the dam, but it can also be an entirely artificial reservoir.
You could probably add a small hydrogen storage facility to every wind farm in the UK for less than the cost of the public inquiry into a new pumped storage scheme.