I thought that this book was going to be about importance of language play to human life, but once I dug into the book, I found that it consists almost entirely of examples of different language games, without much evidence or analysis regarding how or why these games are actually important.
The first 2/3 of the book reads more like a catalog of word games than a discussion about the importance of language play. The background information provided about the games also feels rather thin -- the author tells you only a little bit about the history of some games without much development. Furthermore, readers will already be familiar with most of the games presented, so there's little new to learn.
Thankfully, the chapters on childhood language learning finally provided some actual research information on the topic, and finally built up an argument about how language play is critical to a person's development. In my opinion, the interesting stuff in the last 1/3 of the book is probably not worth the price.