Worth noting that you can use the "thumbs up" button at the top left of the viewer to mark your mark your favourite images. We're planning our browse/review interface next week and this will include an area where volunteers can go back and look through these bookmarked images.
I wonder if it would also be useful to create group albums? For example, Magicians and Conjuring, where all volunteers are able to add to/view that album. This idea of flagging up particular sets of images has come up a few times now so perhaps this would be an interesting way of encouraging collaboration and further help researchers. What do you think?