I like this book. I got it after struggling with some books on quantum field theory and finding myself unable to answer basic self-asked questions like "what is a spinor?". I went through the first 8 chapters and will go back and finish it some day. It's almost all math, very few explicit physics applications (apart from an interesting introduction in Chapter 1) which seems to upset some of the other reviewers, but I enjoyed it anyway. Group theory is beautiful and logical, and Professor Tung's exposition is concise and elegant. He doesn't waste any words and the notation is dense, which also seems to upset some of the other reviewers, but hey, that's math for you. If you would like to learn the essentials of the groups used in physics, this book will do the trick. You can then go back to the physics books for the applications.
P.S. I was only able to find a single typo!