I don't get this at all
Currency is already essentially digital - the banks store your balance in computers, not vaults.
If they mean crypto currency, I can't see the advantage for legitimate transactions (except of course the permanent record in the block chain).
Then there's the extravagant cost of creating the currency. It was recently reported in El Reg that 100 kW/h yields around £3 in Bitcoin. As 1 kW/h costs (retail) about 15p in the UK, £1 in bitcoin would cost about 15 quid to generate, which is why folks steal electricity (or other peoples' computing power, which is essentially the same thing) to do it. As a national currency base has to be in the order of billions, this could get pretty expensive, even at preferential wholesale prices.
I can only assume (with my cynic hat on) that the speculators have a lot of political influence.