Not a reliable text for factual information.
Anybody who has watched a Discovery Channel special knows that things shaped like vulvas are quite common in ancient cultures. Fact. The problem is they chose a bunch of objects for their example photos that could just as likely be penises if you just flip them over. And, again, if you've flipped on the Discovery Channel a few times, you know that's just as likely.
The authors make conjectures of matriarchal societies. This is believable as there are plenty of matriarchal societies in history. But all these matriarchal societies were also peaceful, according to the authors. They claim that there were no weapons found in the cave paintings. And though they did find weapons, they claim they were only used on animals. That's a nice theory, but where's the proof?
The deliberate misinterpretation of common mythology from Egypt, Greece, and even Christianity is absolutely inexcusable. The one that immediately caught my attention was the claim that the Virgin Mary was a "war goddess" just because her image had been pinned to banners during wars, when it's well-documented that she was used specifically for purposes of protection. Not just by Christian, but also by Muslims.
Let me be clear: I don't like the authors blatant misinterpretation of well-known facts and purposeful misconstruing of them to fit their own agenda. To suggest that the Virgin Mary could be considered a war goddess due to being pinned on war banners would be acceptable. Making a statement that she is a war goddess due to be being pinned on war banners is not.
What it comes down to is that they make tons of claims, but cannot substantiate them in any way, which is completely different than presenting theories.
If you need any more proof of the authors' bias, consider the fact that they only choose to cover "moon" goddesses and never make mention of any of the many "sun" goddesses. Sun goddesses don't fit into the moon and menstrual cycle idea that's so popular.
This book is good if you are looking for a different interpretation of mythology. If what you are looking for is something factual, skip it.
For a more balanced view of goddess, I would suggest Rosemary Radford Ruether's "Goddesses and the Divine Feminine".