As an atheist and freethinker, I try to check out any "big" books on the subjects, especially by big-name authors. About a year ago, Divinity of Doubt came out, written by Vincent Bugliosi. In it, Bugliosi, the man who prosecuted OJ Simpson, argues that agnosticism is the only sensible answer when it comes to the question of God's existence.
I don't even really disagree with that sentiment. Not many people who call themselves atheists would even say that they KNOW that God doesn't exist, just that, given the evidence that we have, there's no good reason to believe that he/she/it does. Most atheists would probably be agnostics, given Bugliosi's definitions.
I have two main problems (so far) with Divinity of Doubt. Firstly, Bugliosi misrepresents atheism's top thinkers -- Christopher Hitchens, Richard Dawkins, and Sam Harris. In examining their major works on the subject of atheism (Hitchens' God is Not Great, Dawkins' The God Delusion, and Harris' The End of Faith), Bugliosi doesn't even seem to understand what they were trying to accomplish. He seems disappointed that Hitchens and Harris aren't actually making an argument for atheism (they're actually just describing ways in which they think organized religion is harmful). In the case of Dawkins, he most certainly makes his case for why he doesn't think there is a God; it's just that Bugliosi doesn't agree with that case.
Secondly, it's obvious that Bugliosi doesn't have even a basic, layman's understanding of evolution and cosmology. Some of his statements on these subjects (which are of great importance in the God debate) are embarrassing, particularly when it comes to evolution. He even uses the old creationist standby: "If we evolved from monkeys, why are there still monkeys?!" He does this while even quoting Darwin as saying that man and ape evolved from a common, ape-like ancestor. In other words, nothing in evolution says we evolved from monkeys.
Most of the book seems to focus on why theism is an incorrect answer to the God question, and for his arguments there he's using many of the same tactics that actual atheists use to disprove the ideas and concepts of organized religions. I haven't finished the book yet, so I may write more when I have. Hopefully I'll get past the cringe-inducing scientific ignorance parts soon enough.