One positive side of a world without photographs would probably be that it would have the effect of making people pay more attention to things they experience. I can remember many times going to some beautiful place, and spending more time concentrating on taking a good picture than actually seeing where I was and taking it in.
Without photos, the world would be very different in many negative ways as well, and it is hard to imagine what it would be like without picturing a society that was really far behind in technological advancements. I have to picture in my head different time periods or third-world countries to try to understand it. Living without photos just makes me think of a harder way of life.

A photograph, to me, is just a way to capture a moment, person, or place in order to use it for reference later. It also has to capture it by way of light exposing something.