Here's Mark Pesce talking about social media (Twitter especially) being used in similar ways.
You better believe the cops (and any other group or individual with anything to hide) will be trying to confiscate or legislate against cameras in the hands of individuals in the future. My advice is to invest in cameras that can be concealed, and cameras that can stream video live to the internet, so that even if it is confiscated they won't get the bits before they're out in the wild.
Sites like ustream.tv and justin.tv are making it a lot easier to stream video from a computer and the unfortunately named brainchild of wearable computing pioneer Steve Mann, glogger.mobi is doing the same for smartphones. There's still the old standby of snapping a pic on your phone and emailing it to flickr or your blog.
A quote from Accelerando, by Charles Stross (free online)
"Manfred's on the road again, making strangers rich.
It's a hot summer Tuesday, and he's standing in the plaza in front of the Centraal Station with his eyeballs powered up and the sunlight jangling off the canal, motor scooters and kamikaze cyclists whizzing past and tourists chattering on every side. The square smells of water and dirt and hot metal and the fart-laden exhaust fumes of cold catalytic converters; the bells of trams ding in the background, and birds flock overhead. He glances up and grabs a pigeon, crops the shot, and squirts it at his weblog to show he's arrived. The bandwidth is good here, he realizes; and it's not just the bandwidth, it's the whole scene. Amsterdam is making him feel wanted already, even though he's fresh off the train from Schiphol: He's infected with the dynamic optimism of another time zone, another city. If the mood holds, someone out there is going to become very rich indeed.
He wonders who it's going to be."Also, Mr Lee has a Catcam