Apple quietly announced after its iPhone 7 event on Wednesday that MacOS Sierra will officially release for Macs later this month.
The Cupertino, CA-based company's latest desktop operating system will start to roll out 20 September, according to its website. This is the first desktop OS to have Apple's new naming scheme, and it marks the retirement of OS X. The idea is that MacOS will better align with WatchOS and tvOS, Apple's operating systems for Apple Watch and the fourth-generation Apple TV, respectively.
On 8 September, Apple released the golden master (GM) build of MacOS Sierra. A GM is typically the final build of a piece of software in the beta stages for developers. In terms of MacOS, the GM build arrives shortly before the official release that's delivered to consumers. Apple is pushing out the GM build two weeks after its seventh MacOS Sierra public beta and less than two weeks before the official release for consumers.
In other words: the MacOS Sierra golden master - if there are no critical bugs found - should be the same piece of software that most Mac owners can begin downloading later this month. If you'd like to try the GM, you must be a beta tester in Apple's beta testing programme. You'll receive the macOS Sierra golden master through the Software Update mechanism in the Mac App Store.
The MacOS Sierra is a major update with a number of new features, including Siri for the Mac, new Continuity features, and a "Universal Clipboard". There's also deeper iCloud integration, new Photos features, and an improved Messages app, among other things.