Photographs Not Taken, by Will Steacy. This a great collection of essays by 60 photographers about photographs they never took. It's fascinating how each essay is unique, how personal each story is. Yet, no matter how different each essay is there are threads that connect every artist across the whole book; at the core of every photograph not taken lays a technical hurdle, a logistical problem, an ethical dilemma, and more often than not a stroke of compassion masked as a question of "courage." More importantly, almost every photographer ends up drawing the conclusion that some things in life are so important that they must be experienced with our own eyes and must forever live in the most permanent photographic medium: our memory. I highly recommend it, my favorite essay was Amy Elkins', you can also listen to her read it on tape. Every photographer out there has a photograph not taken.
Believing is Seeing by Errol Morris. In this wonderful book (designed by Pentagram), Academy Award winner Errol Morris questions the truth in photographs, making his way through different photographic mysteries and questioning the validity of certain decisions made by photographers in order to convey certain truths. I am not done with the book just yet, but his writing style is very intimate and I love the seriousness with which he has set out to get his answers.