Here's my take on it. I been an RC modeller for nearly 30 years and built and flown every single type of aircraft there is. From simple 4 channel trainers right up to 1/3 scale 45Lb P-47 and everything in between.
In 2003 there was a young girl killed by a trainer at an uncontrolled, no club, public flying heathland site.
http://www.dailymail.co.uk/news/article-177139/Teenager-killed-hit-model-plane.html
The incident was about 5 miles from our well controlled and well run club site. The public flying site had no rules, no control and anyone could take anything and fly. They did not need insurance, training, advice or guidance. The site was open to to the public. Dog walkers, motorbikes, joggers, pinicers etc
The place was an accident waiting to happen.
There was some press fallout locally, the story came and went and that was it.
Just before that was a young lad killed at a model show
http://news.bbc.co.uk/1/hi/uk/503181.stm
The trouble with quadcopters, Phantoms in particular, is that they are so easy to fly, therefore, anyone can get one and fly it. You don't really need training to fly and therefore a skill level and because they are easy to fly, people won't join "clubs" to get help and advice. So I reckon Quadcopter flying is a very singular hobby. People won't and don't see the relative dangers of flying in local parks, over major roads, near built up areas etc.
A Phantom weighing 3-4Lb coming down has the potential to hurt someone, but a model aircraft doing 50-60mph and an IC engine on the front doing 18k revs with a razor sharp carbon prop on IS going to really hurt (or kill).
I strong advice anyone to join the BMFA, get their insurance. They represent modelers in the UK and they've done ok up till now.