Well, not really The Truth. That's kind of the point. This book argues that The Truth is there is no Truth, just observation.
But it's just so nice to read a book where everything I've ever thought about religion has been expressed with considerable more force, and significantly more eloquence than I've ever been able to muster. While Dawkins does use a little more invective than is helpful, I can't honestly see these "massive holes in his thinking" which everyone goes on about. Either you agree with the logic of his arguments, or you don't.
Now, I'm not remotely arguing that Dawkins has the answers... but he is the only man who's had the bottle to stand up and attack things which I feel need attacking. It really is the case that atheism IS, by it's very nature, an attack on religion. To be an atheist is to actively reject religion, not to compromise and say "well, maybe some of it". If you still believe some of the supernatural stuff, you're not atheist, you're agnostic. And why shouldn't Dawkins want to shout his beliefs from the rooftops? Atheism has as much right to do so as any other belief system.
I enjoyed this book; but then, I was always going to. It's never difficult, preaching to the choir (irony intended). If you're like me, a secular atheist (who grew up as a child listening to religion, terrified of patent nonsense, but lacking the courage, not the belief, to face it down) you may well like this. It's a great book if you actively dislike religion.
If you're an agnostic, you may find it a little overly strident in it's assertions. As I say, there's a lot of invective.
If you're religious, it's probably not for you; Dawkins is quite happy to insult the religious at every turn (for strongly heartfelt moral reasons). I would suggest only read it if you're not fixedly religious. It will just annoy you otherwise (and you'll feel very insulted to boot).
Personally, I think that irony that Dawkins is attacking religion from his moral convictions alone is a good enough reason to make this one of my favourite books.