Hmm, "Smart Meter" is the only name I've heard for them, and it wouldn't occur to them to conceal this as most people don't understand it's potentially a Bad Thing.
(There were also some early experimental meters which also got called Smart Meters, also with big displays and a detailed record of your usage throughout the day, but no remote programming.)
The call centre bod may be able to tell you if it's a Smart Meter, but won't know anything about the problems with them.
In fact, the official line from Ofgem and everyone else involved seems to be:
a) smile, it's all wonderful for you, and besides
b) STFU, we're going to do it anyway.
If you want some time to find out more and regroup, perhaps you could claim the appointment is no longer convenient and let them make a new date in a month.
We really need to know the legal procedure here. It might be that if every householder refused entry and they had to obtain individual court warrants for every house, the cost would seriously derail the rollout.
I should start a thread about Smart Meters, shouldn't I? The whole subject gives me high blood pressure...