This book fails to live up to the promise of its title. It does not contain 50 arguments in favour of God.
The book is presented in four sections, which I will briefly comment on, in turn:
Philosophy (Chapters 1-7): The cosmological argument (chapter 1) and the moral argument (chapter 2) are good, well established arguments in favour of a deistic God. There are much better books out there on these, but this book functions as a primer. From there things go a little downhill. The next few chapters muddle through the 'evidence' of near death experiences (not compelling at all) and make some points about suffering and the problem of evil, but these are not presented as evidence for God, but rather as defence against atheist arguments. Chapter 5, in particular, offers no evidence for anything, I think it tries to explain that Christians suffer in significantly different ways to non-Christians, so therefore there must be something in Christianity, but it completely fails to demonstrate that Christian suffering is in any way different to non-Christian suffering.
After 7 chapters, only 2 arguments for God.
Science (Chapters 8-26): This is the longest and most tedious section of the book. The majority of these chapters deal with Intelligent Design (ID) arguments, which all boil down to 'irreducible complexity'. I'll grant that this is a strong argument for a deistic creator, but this is repeated in multiple chapters, again and again in slightly different ways. In addition to the ID stuff, the best argument for design here is Chapter 10, which addresses the fact that the three things we need for life (oxygen, water and light) are all, fundamentally, toxic and all organisms have very clever ways of dealing with the negative effects. I found that one fascinating. Also in here are chapters discussing the Copernican revolution (Chapter 9) and an odd chapter (8) which asserts the need for God's ongoing tinkering with creation, while providing no evidence of it. The science section degenerates into a few final chapters which give the ID proponent ammunition against 'Darwinists'. The implication being that if you can find a hole in the theory of evolution, then the opposition (assumed to be ID) wins by default. This is not science, it is not evidence, it is politics. I came out of reading this section very, very annoyed.
After 26 chapters, only 4 arguments for God.
Jesus (Chapters 27-42): While there are many arguments in this section, they all fundamentally rest on the assumption that the non-miraculous claims made in the new testament are all reliable history. If you accept all the non-miraculous claims as fact and accurately described, then you can deduce that the miraculous claims also happened. No attempt is made to defend the claim that the stories are historically reliable, other than the fallacious appeal to majority - "the majority of biblical scholars agree..." - the fact that the majority of biblical scholars are Christians is not considered or its implications discussed. Was Jesus resurrected? Well, the evidence of the gospels seems to suggest this. But. The gospels were expressly written to defend this very claim in the first place, so it is not surprising that they suggest it! Some 'secular' evidence is presented and discussed, but all this shows is that there were "Christians" at various times, some decades after the time of Christ, not that their beliefs were true. (In a similar way, we could show that there were Muslims some decades after the death of Mohammed, but would Christians accept that as evidence for the truth of the Koran? I doubt it.)
Its hard to select genuine 'evidence' in those 16 chapters, but I'll concede there's probably two or three good arguments, so:
After 42 chapters, only 7 arguments for God.
The Bible (Chapters 43-50): This is a rag-tag bunch of chapters tagged on the end because they don't really fit anywhere else. Some of them are clearly not evidence for God, for example, "Why all the translations?" (Chapter 44) but I'll grant that the archeology chapter (45), while it does restrict itself to the new testament only, does have some evidence in it. Not greatly compelling evidence of much, but that's not the point. Being generous, I'd grant 3 pieces of evidence in this section, so:
After 50 chapters, only 10 arguments for God.
This book would have been much better if it had realised its own limitations and focused on the 20% of reasonably compelling arguments it has, rather than wasting time, effort, and pages upon pages of text on the 80% of padding in here.
One thing is clear from reading this, it is only intended for an already committed Christian readership. Nothing in here will convince the skeptic. The point of this book is to make the Christian feel good about their own beliefs without really questioning them. The point of some of the chapters in here may be summed up as "look, some really, really, cleaver people have already thought through these issues, so you don't have to."
Whoever you are, and whatever your pre-existent beliefs, I would not recommend you read this book. It is not what it claims to be on the cover. If you want to read about ID, there are better books out there specifically on that topic, if you want to read about the philosophical arguments, there are better books out there, and so on. This book attempts to show that the evidence for God is compelling simply by weight of words, without really ever wresting with the tricky issues.
As a doubting Christian who is struggling with reconciling belief in God with the strong arguments made (and evidence presented) by some of the "New Atheist" crowd, I found this book lacking in weight. It is no good as a counter argument. If this is the best that Christianity has to offer in favour of God, then it is clear that the majority of Christians never seriously question their own beliefs.