How can we be sure that the photography is of the actual event, and that it is original? This sounds like a semi-automated mturk job - there will have to be manual aspects to the oracles.
I am most interested in world improving efforts like planting trees and following up with them. Having oracles verify good deeds sounds like a really fun job that has the potential to change the world.
Well for example suppose you want a photograph of something which hasn't happened yet?
Oh fantastic. I am already seeing the revolution in news journalism with your example!
The 'job' must be declared, with certain specifications, as well as maximum entries I suspect. The oracles can process metadata for gps locations and a bit more information, can use certain image algorithms to sort faces, perhaps other text in photos, but will still need to manually review the filtered entries at some point.
There will be work involved or the oracles would be terminat....I mean friendly androids!