Cycling on the pavements can definitely be menacing and dangerous to pedestrians. I've been sworn at for stopping and turning suddenly and not hearing a cyclist riding close behind me - my daring to be a pedestrian on the pavement forced the cyclist to brake. I suppose I'm lucky they did, or they would have crashed into me.

Face the facts; there is a real problem.
Most modern bikes are silent, you can't hear them behind you and why should I have to share the pavements with them? If they're not prepared to cycle on the road then they shouldn't have a bike in the first place.

I get really annoyed when I see pedestrian's legitimate concerns being belittled. And just because the police can't or won't deal with it effectively doesn't mean it isn't a danger. Try walking through Hyde Park and watch how many ignore the 'no cycling' signs. There are clearly marked cycle paths but they still ignore them and choose pedestrian only paths instead.