There's been a bit of an outcry here in France where they've been installing these things for the past couple of years.
People are refusing them for various reasons including increased electro-magnetic radiation from the wiring within your house and the "spying" element. Smart meters can obtain data from increasingly "smart" appliances (TVs, coffee machines, ovens, etc.) and people are objecting to the possibilty of the electricity provider(s) selling this data to interested third parties.
The deal here is that, for the moment, they can't oblige you to change your meter, but if you do it just now it's free, otherwise you'll be forced to do it in the future and will be charged a few hundred quid (IIRC).
I just went with the flow and got one installed and to be honest the online access to our usage figures (daily, weekly, monthly, etc.) is prettty handy.
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