This book describes all significant changes in the language and the Standard Library. What's more, it provides a lot of practical examples so you can quickly apply the knowledge to your code. https://leanpub.com/cpp17indetail
Surely this is supposed to be "deprecation"? Unless there's something about C++17 that is decreasing in value...
In general, the free chapter at least looks good content-wise, but really needs another couple of editing passes IMO to clear up some weird/clunky grammar.