Some companies that I have worked for have utilized them and some have not.

At some, they were managed by IT and at others they were mananged by Physical Security (which was part of a large IT organization).

At some places they were superfluous, at others they were essential.

I think they are fine, in the workplace.

Outside the workplace, I don't think they are very useful.

CCTV stops only one group of people from committing crimes: those that are VERY unlikely to in the first place.

Yes, there are many cases where it helped solve crimes, but I think they are a weak link.

I think law enforcement learns to rely on them to police crime for them (it's just human nature).

I think it offers people a false sense of security. As I said, it isn't going to stop a violent criminal from killing you. It might help the police in punishing him for doing so, but that is little consolation to you (the person that is already dead).

The simple fact that only five percent of these cameras are in compliance with law should say a great deal about their usefulness (or lack thereof) and their flaws.