I think its a good idea for members uploading photos to copyright them using the Creative Commons licence. CC is great for not only protecting your work but also you may be able to get credit by third party users if you so wish by restricting your photos use.
If you think your photo is good or could be marketed by a third party then CC is the way to go. Its free too.
Press Select Licence button and copy the code into the "Description" box when you go to edit your photo information.