First let me state that, as with most O'Reilly books, there is nothing wrong with the writing in here. Topic coverage at least goes deep enough on each article to let you decide if you want to go any further on your own. Some articles mearly cover CPAN module and there are better places to get that kind of material, I think. Coverage of Obfuscation is pretty substantial, if you enjoy that sort of thing (I don't). Still the articles themselves are solid.
Unfortunately, I didn't really enjoy the book, in spite of the above. Honestly, I think it's the title. I'm a big gamer who plays pretty much everything and I bought this book expecting to get some gaming content for my favorite programming language. (Note the first word of the title, "Games".) If that's what your looking for too, look on, it's not here. The book has four chapters covering game related material. The first mainly covers the game tool modules available from CPAN and that is sadly slim pickins. The second describes a contest the Perl Journal held and was one of my two favorite chapters in the whole book. The third is all about the Perl Z-Machine "rezrov", which is at least a little informative. The fourth is How to Build a TK Card Game. That's it, for gaming material, be warned.
The book mainly focuses on random aspects of linguistic theory, including NPL. If that's what you're after, this is the book for you.