Dan Gravell wrote in message ...
My thoughts...

1) Taxis will become significantly slower than minicabs, and so will become
a distress purchase for people who can't get a minicab. People will prefer
any minicab, even an illegal one, to a taxi.

I think the general trend is to fit these things to all cars in London,
or at least that's what I read.

What and lose all that revenue from Speed Cameras. I can't see that happening :-)