There was a little controversy over Carnage with my Students' Union at Uni, they were worried about the safety of students as previous Carnage events had resulted quite badly for some areas and whilst obviously they couldn't ban it or force students away they were trying to encourage people from not going. At the time I was on the executive committee at the time, so I had to go to a meeting which was basically about 'how are we going to deal with Carnage?' There was plenty of police on the streets.
However, as far as the facts went, it was at times a little difficult to tell the difference between the sensationalism within the SU and the actual hard cold facts. This was 3 years ago mind you.
I didn't go, but my night outs were either organised by mates or just on the basis of "I feel like going out".