The one thing that I really liked about this book was that despite it being written by a Christian, it was incredibly objective (though it is difficult to be objective with Christianity when one is a Christian). A lot of books on religions that I have read, that have been written by Christians, tend to pretty much bag the other religions and then really talk up Christianity. Dickson doesn't do this, rather he tries an objective approach so that those who read this book and make up their own mind.
Now, I am a Christian, so when I read this book, it ended up messing with my head. All of the sudden, Hinduism and Buddism made perfect sense. In fact the Christian concept of hell, as I understood it, could be similar to the Buddhist concept of Nirvana. In fact, so could the Hindu afterlife as well. However, I now doubt that Hell and Nirvana can be considered the same (but I thought so back then). In fact, after reading this book, Buddhism suddenly became very appealing (which horrified my small group leader).
Being a Christian makes me very exclusive, however this is the theme of Dickson's book: all religions simply cannot be the same. They are simply not compatible (well, Buddhism could be, but pure Buddhism is more of an atheistic philosophy than a religion), and while we may preach toleration (and I try to be tolerant to other's beliefs) those of us who cite that all religions are the same really have not looked deep enough into these religions to see the differences.
I guess that is why Dickson doesn't attack any of the other religions, because his purpose is not to promote Christianity (he does that in other books), nor to prove the authenticity of Christianity (once again he does that in other books) but rather to challenge the idea that all religions are the same. I agree with Dickson, they are not (okay, in ancient times they may have been, but that is no longer the case). The other thing that I like about this book is that it teaches me about these other religions, though I would be more interested in knowing about a lot of the minor ones.