I don't care about photos!
I think it would be cool if you could hold down the Ghost button (Back/Select Button) and you would go into a camera mode, where you see the game through the perspective of the Ghost and be able rotate the camera in any direction to take a photo. It would be pretty awesome to be able to take a photo of your Guardian and then maybe have a couple friends behind you doing some awesome poses. I also see alot of people taking screenshots of the scenery of Destiny or just any other awesome things in general. Maybe, you could use a free-cam when you enter this mode too, allowing you to fly around as the Ghost to take awesome screenshots of the game. This would really enhance the social aspect because you could take these photos in Destiny and then share them with friends, clans or the community.