Yesterday, Apple released the ninth developer betas for iOS 11 and tvOS 11, and today, the ninth build of macOS 10.13 High Sierra is available. The build number is 17A360a, and it doesn"t contain any new front-facing features; instead, it focuses on fixes as Apple finalizes the new version of the OS.
There are still some known issues. Most notably, HDD-only Macs and iMacs with 3TB Fusion drives and BootCamp aren"t supported for the new Apple File System (APFS). Presumably, that"s not going to change at this point.
Apple began sending out invitations yesterday for its next major event on September 12, where the firm is likely to announce a trio of new iPhones, an Apple Watch Series 3 that supports cellular connectivity, and an Apple TV that supports 4K and HDR. Afterwards, it will release GM seeds of its four major operating systems to those that have been beta testing them, followed by a public release a couple of weeks later.
This will likely be the last beta of macOS before that happens, although it seems likely that we might see a ninth build of watchOS 4.