An intriguing article in the Washington Post recounts a handful of copyright abuse cases in which corporations have used photographs taken by amateurs and published online, for example in their blogs or on social networking websites. There's a curiously ambiguous thread to the piece: on the one hand it says perhaps people shouldn't publish material online if they don't want it to be copied and used elsewhere, while on the other it notes that people are increasingly calling their lawyers to defend their rights. It is strongly implied that corporations should know better, in other words there's a David and Goliath element to it, especially if the self-same corporations are quick to defend their own copyright material against abuse by others.
Blogs and other online social interactions are credited with informing people that their images are being abused, and helping them defend their rights. Online communication between people is definitely changing the nature of human culture. How else could loose-knit communities spread across various countries collaborate with such ease?
Copyright law makes no distinction between original materials created/published/used by amateurs versus professionals. Anyone who uses images and other original materials in their own work either needs explicit permission from the copyright owner (for example through a license agreement or contract) or has to conform to the narrow "fair use" provisions (at least in countries that allow "fair use" - I gather Canada is a notable exception to the norm).
Several of the cases noted involved abuse of images by 'low level employees', corporate-speak for office juniors who are either unaware of, or choose to ignore, their copyright obligations. Clearly, corporate security awareness programs should cover copyright and other compliance obligations [as indeed NoticeBored recently did!].