My main gripe about this book is that it is organized in such a fashion that it makes it difficult to outline. The chapters don't develop in a manner that lends itself easily to straightforward interpretation of main ideas. Instead, the authors rely primarily on providing definitions of terms, and then presenting information that is of secondary consequence.
The book is informative, but not linearly coherent.
To address the issues raised by another reviewer about Islam, after some more scrupulous reading of those sections, I believe the reviewer let his anger get the best of him. For example, on the section dealing with the "Sour Grapes" reaction, he automatically combined the imposition of pork-eating taboos with the "sour grapes" reaction, which the authors clearly didn't do. They develop the idea and geographical importance of pork-eating, and gives the "sour grapes" reaction as a possible explanation to the eschewing of pork--and they offer others as well. The idea was to show that we don't know where it began, from a cultural stance. The author attaches from an early stage that eschewing pork was part of Judaism, a much older tradition than Islam or Christianity, and makes the point that the distribution of the taboo follows in line with areas that pork isn't easy to cultivate, since a nomadic lifestyle is not suitable for pork farming.
Note that this is different than saying "Islamic people made conquered peoples eschew pork because Islamic people were jealous of those who raised pork." This statement is almost nonsensical, but if you were to simplify the claim raised by the other reviewer, this is what you get.
Did later islamic kingdoms impose the non-eating of pork in the regions of Babylon and those cities near rivers? Yes they did. The author was wrong to use the language of "for revenge," as it puts a slightly moral stance on the books position, and does paint Islam in a negative light--which a good textbook shouldn't do.
And in dealing with the oft-violent histories of all three monotheist religions, the authors spent a great deal of time on the christian enslavement and mistreatment of Indians by the sword here in the Americas--showing that Christians did bad things in the name of their faith, just as Muslims did.
As far as religions go however, the treatment of buddhism and hinduism is even more sparse than it is on Islam, though I have yet to read a western-written book that covers eastern traditions in an interesting fashion. Most of them have a sudden style-shift from seeming interested in the subject matter to suddenly seeming more like an encyclopaedic regurgitation of well-known facts.
This book is guilty of this as well. Docked one star for its non-linear style, and one star for its poor treatment of eastern religions.