A lot of recipes that are ready to use in your project or at least you can get more ideas if you stuck.
The authors don't focus on explaining what all functions do in deep details so this might be hard for beginners but even they can understand what's going on in the code.
Code examples are really simple, without unneeded html or js lines so you've got clear view. If you want to learn jQuery then this book is for you, if you know jQuery well this book is also for you just to refresh your knowledge or learn some new solutions.
Personally I like two things in this book: 1. No screenshots - so if you want to see what this code does you need to write it, great way of learning! 2. "please externalize this code to an external .js file" - this comment you will find in every code example until chapter 9 and imo it's important to remind people to not attach js code in html file.
I definitely recommend this book for beginners and advanced users!