Yes, it would allow some cost reductions by firing meter readers. Whilst I sympathise with those losing their jobs, do we really need to provide employment by keeping things inefficient?
Also it would be possible to allow the consumer to configure their smart meter (via the web) to switch between alternative generating sources (i.e. renewable, nuclear, coal, gas) according to the relative spot price of each source rather than (or in addition to) switching between supply/distribution companies. Those keen on renewables, for example, could set their meters to only switch away from the renewable tariff to one of the others when the non-renewable tariff is 80% of the renewable tariff (or choose your preferred generating source and price premium).
This would cut costs by getting rid of the administrative burden of price comparison/switching web sites and the legions of doorstep (mis)sellers, But again, that would mean job losses.
Proper regulation is needed to get rid of the plethora of confusing tariffs, and cap unit prices to pass on cost savings to the consumer. Maybe re-nationalise the whole edifice and cut out the administrative duplication of dozens of chief executives, sales teams, head office buildings etc.