I picked up this book - as I imagine many will - knowing the previous works and essays of Grayling (including his contributions to Prospect magazine). It is certainly a quick read but covers a lot of ground. Even though the price did catch my eye for what is a fairly short book (although it is in hardback which adds a few pennies), I feel such a book - that you are likely to return and refer to - is certainly worth it.
Grayling is one our greatest contemporary philosophers - and this book adds detail to his views on religion and the current debates about it. The chapters are individually very interesting (particularly the one regarding Bertrand Russell) and flow well together. For those who are not familiar with Grayling, he does fall into the Harris, Dennett, Dawkins and Hitchens side of the debates regarding religion; I actually think this book supplements the God Delusion (Richard Dawkins) and God Is Not Great (Christopher Hitchens) very well - it is almost a summary of their main points, but, importantly, it adds Grayling's own ideas, knowledge and commentary. The discussions, arguments and indeed the writing style read clearly, intelligently and have huge relevance in the world.
I would recommend this to anyone with an interest in philosophy or even politics and current affairs - particularly where religion is concerned (such as the rise of Islamic fundamentalism, Creationism and Intelligent Design). Grayling's excellence as a writer and thinker shine throughout, as it does in many of his other works (which I also highly recommend!)