One common misunderstanding about copyright is that online content is not protected by copyright. Not true! Even if the content is posted without a copyright notice or other copyright information, that content should be presumed to be protected by copyright.
The same copyright principles apply to photographs posted on Flickr. In a recent situation, Toyota U.S.A. posted some photos on one of its Web sites — photos it obtained from the photography site, Flickr — without permission of the photographers. Toyota has now made a public apology and has removed the photographs. Lesson for all: get permission when using content from Flickr and other online venues.
Further information on this case at: http://www.pdnpulse.com/2009/11/toyota-apologizes-for-using-flickr-photos-in-suv-ad.html.