Susan Sontag makes several points in this chapter of her book. The one I've found most interesting is that she takes the time to exclaim that the majority of the photography world has been overrun with photographers that are not artists. This isn't to say that these people are not true photographers or other whatnot.
The image I have posted is actually an image of the author, Susan Sontag. It illustrates her point--photographs are being used much more commonly to convey less a message and more average information, though it is still plain to see after moments that it is not just a profile picture. There is emotion in her face. There is a certain attitude about the lighting of the room. Everything in a photograph will always give information beyond that which was in front of the camera, and thus shape the attitude and moral and ethical standings of its viewers.
Yeah. That just happened.