If you like misery then this book is for you. McCarthy rips everything out of the novel--punctuation, names, chapters, color, etc...--and uses only what is needed to an effect that will make you want to slit your wrists and hope for death. The only colors are shades of gray. There is no happiness or hope, even despite the smidgen of hope at the very end. And it is a shame because Cormac McCarthy is an amazing writer with talent and a sense of story that I have not seen is years. He understands what makes a reader turn the page, plotting, timing, mood and voice. And although the writing is absolutely amazing, the book has very little depth.
This is the story about the love of a father for his son, which can be told in a much more positive way. Misery DOES NOT equal depth. This book is not deep. It shows humanity at its worse and tries to make the reader feel as if this is what people are all about. And although I feel that every writer should read this book, it's not for the subject mater but for the control of language and the artistry of writing.
If you want a great, well-written post apocalyptic book read The Stand by Stephen King. The Stand has depth and real insight into the human condition. The Road is a piece of amazingly well written crap.