It's interesting to read a book with which I disagree with almost every single word. But unlike the recent spate of pro-God responses to Richard Dawkins, at least Williams makes a decent stab at an argument. There are plenty of holes though. Williams thinks that the only way there could be objective meaning in the universe would be through God. This is false in two directions. First, unlikely though it would be, the human race may have been manufactured by an alien race and given a purpose without the need of a God. Second, even with a God, there is no reason to think that our lives would have objective meaning. As cogs in God's machine, it's difficult to see why this would generate any more meaning than being cogs in a God-less machine.
More criminally, Williams makes the same mistake that CS Lewis does. He provides pro-God arguments and then leaps to the assumption of a Christian God without providing any arguments to bridge the gaping chasm between these two claims. But what argument could he seriously have offered? Any claim that the Bible is the Truth because it tells you so is circular. Any claim regarding personal faith would apply equally to believers of all other faiths. Best just not to mention it and hope no one notices.
I was reading this book mostly for the pro-objective meaning and pro-objective morality arguments it espouses in the first few chapters for a couple of essays I was writing at the time. Nothing it contains offered any serious challenge to the anti-objective meaning and anti-objective morality stance I was already taking, but it's worth a read though.