Well this book is either impressive for its honesty or embarrassing in its self-absorption. Either way, its interesting having someone articulate each step of their thought processes as they take a journey through a sweeping life change.
I think intelligent people of faith would find this book deeply rewarding, but it is unlikely to convert an atheist reader. In particular, it's hard to swallow his basic premise: that the only possible option for confronting the absurdity of existence is despair. Camus would disagree, I think. I'd say that to experience absurdity in despair is the same as experiencing it as the absence of God, in which case the whole argument is just begging the question.
Fascinating reading, though.