Description:This is really not a very academic reference. I am by no means a linguist, but I must say, there was very little of use in this book that I did not already know. With all due respect to the author, most people are really going to get less out of the articles in this book than out of wikipedia articles for the same languages. This is the unfortunate reality of the new information universe---information like this is really inferior when presented within the confines of book form, nowadays.
For what it is, though, it is fine. But if you are interested in more than how many people speak a language and where it is spoken, you'll really want to choose a different book. And if you ARE interested in how many people speak a language and where it is spoken, then you know where to find such information---there is no need to buy this book.
With all due respect to the author(s) of this book (which I am sure was a terrific effort to compile)---this book would have been great and relevant ten years ago. But with the other options nowadays available for anyone looking for "encyclopedic" knowledge of a subejct, it just falls flat.