There's a lot of debate right now about the right to take pictures in public - especially in the UK - where it seems that authorities as well as the public has grown an irrational angst for people taking pictures.
Pedophilia, terror (and paparazzi for the few and famous) seems to be the main driving forces behind a row of incidents where photographers have been harassed in the streets, on playgrounds or in other public places for taking completely innocent pictures or videos.
Add to the the increasing protection of private property, registered brands and copyrighted material, and soon you won't be able to point your camera anywhere without a permission. I recall my girlfriend wanting to take pictures of some impressing sprockets in the London Underground with her small P&S. Not as soon as she had it out, a security guard approached her and told her not to. I myself was asked to delete images from my SLR in a Publix supermarket in Florida recently by two very officially looking guys. I deleted my pictures in front of them - and undeleted them in the car 10 minutes later. And while I was stopped my girlfriend shot away with her P&S.
I like to take pictures in the harbor area of Copenhagen, but recently any cruiser that embarks there will have a shipload of fences and signs saying "No photography!". I usually bring a large camera on a tripod and have never been stopped in my creative endeavors.
All this to say that the banning of photography is like trying to stop waves from rolling or rain from falling. The world is flooding with cameras these days, and in any big city crowd I would guess that 50% or more people are carrying a camera - in phones, P&S's and larger cameras. There's no way of stopping people taking pictures. And if you want pictures of anything, just do a web search. There's no reason to go out there and risk your limbs. None of the terrorists behind any recent terror acts took any pictures as far as I know.
It's strange that this paranoia over images and photographers come about now where photography is so common. Go down any crowded street in any city in the world, and you will most likely see someone taking a picture.
But still we hear about incidents where authorities or fellow citizens have tried to stop photographers, harassed them and even assaulted them and jailed them. This video from Current TV illustrates this well.
One of my absolute favorite videos, clearly showing the absurdity of this, is the Australian comedy show The Chaser's War on Everything that sent two people out to shoot the Sydney Harbour Bridge. Hilarious.
There are forces trying to stop this development. Photopermit.org has a long row of incidents on record and follows the development around the world. People gather to stand up for their rights like on this
The city of New York has recently put the rules for photography and filming in print (warning: 12 pages of legal mumbo-jumbo in PDF-format), and in spite of the strange wording, it essentially says that you can shoot without permission if you do not obstruct traffic too much or bother the public. In their own words "...standing on a street, walkway of a bridge, sidewalk, or other pedestrian passageway while using a handheld device and not otherwise asserting exclusive use by any means, including physical or verbal, is not activity that requires a permit.".
Handheld... hmm. What about using a tripod? Well, never mind. It essentially says that you can shoot freely in public within reason - like most of us do.