We just finished our book on Advanced Swift, and I think you folks are the perfect crowd. There's also an online preview =). Let me know if you have any questions!
This book goes WAY deeper into the patterns and corner cases of the current language implementations. Like the title says Advanced Swift, ie the book you should read after reading the book from Apple. It does a fantastic job of explaining not only how you might use the features in swift but the effects and patterns features might cause you to use. I say patterns but it's not a design pattern type of book but a advanced language type of book.
The other comment in this thread explains it really well. Another point of view: Apple's book is targeted at all sorts of developers, from complete novices to people who've written ObjC for two decades. We target advanced developers, and assume that you are already a professional developer. That allows us to dive much deeper!
Are you planning to release some updates sections for Swift 3?