macOS Sierra for Users, Administrators, and Developers is a book that covers all of the new features of macOS Sierra. For users, some of the categories covered are the new name, Siri, changes to Photos, the Apple Watch and your Mac, Storage updates, Messages, Safari changes, and the Apple File System (APFS).
For Server Administrators, some of the items include updates to permissions, Apple Classroom, security updates, and other supported changes.
For developers, the changes in Xcode as well as Swift 3 are covered. Along side these, the new frameworks that have been unveiled by Apple are discussed.
No matter what your level of expertise, macOS Sierra for Users, Administrators, and Developers has something for everybody.