Alistair,

This use of someone else' photo without credit is probably unethical but, unfortunately, probably not illegal. As a photographer, people "re-use" my photos all of the time. I used to get mad and make a big stink about it but now the only time I react is if they are using a photo of mint for an obvious commercial purpose. Fair use laws in the US at least generally allow people to use "re-use" copyrighted photos for non-profit educational uses, especially as far as it concerns low res photos on the internet. I don't like it....in fact I hate it....but it is what it is for now and in my opinion the protection of rights on intellectual property will probably only get weaker.

JohnCote