I wouldn't worry too much about speed cameras. A few years back there was an online petition to stop the government from going ahead and installing black boxes in all our cars. I am sure that soon that will happen regardless of whether we want one or not.
I don't think that cameras are the issue here. The real issue is now the lack of real policemen in favour of machines that just record and produce a fine.
The real problem is that technology only captures the honest. If someone has cloned a set of plates, or has removed them completely from their car, the camera system cannot help. It is the same with the black box technique. No criminal is going to raid a post office without first removing the tech from their car.
The current system favours fining those of us who are honest enough to obey the law in principal. The fact that we may be speeding is irrelevant to the fact that we display a legally required number plate.
Many have got away with speeding because they obstruct their plate enough for the ANPR not to be able to read a plate (mud is often used to good effect). To effectively police this country, we need to invest in real people who can make a judgement call, such as to stop a vehicle that has tampered plates, or no plates, and prosecute effectively.
It is all well and good investing in this technology, but it doesn't get passed the point that there is an element who have bypassed this technology through simple plate tampering, or cloning, and there is no one out there seemingly clamping down on this nuisance.