This is an intriguing and useful book.
Useful because it covers important algorithms for website testing in some detail. Intriguing, to me at least, because it can be read in a single sitting and is quite narrowly focused. Further, it is concerned with a fairly technical topic (multiarmed bandit algorithms) - it feels as though the entire book itself would ordinarily be a chapter in an imposing textbook on methods.
I'm by no means an expert on this topic, so I can't quite say how it fares against other resources - but I can say that I feel as though I grasped something important about this class of algorithms from reading this book, and on that basis, recommend it.