Android 7.1 Nougat update for Nexus devices to be rolled out starting December 5
Vodafone Australia has it that Google is planning to release Android 7.1.1 for the Nexus 6P on December 6. The update, weighing in at about 650 MB, will include the December security patch alongside the new features of 7.1.1 Nougat. It may take up to 2 weeks before all eligible devices will get the update.
If the Nexus 6P is getting Android 7.1 on December 6, the Nexus 5X, Nexus 6, Nexus 9, Nexus Player and Pixel C will likely receive the update at about the same time (not just in Australia, of course). As you probably know, the Google Pixel and Pixel XL phones already run Android 7.1, but they, too, will receive updates in early December, since they need to get their monthly security patches.
An Android 7.1 Developer Preview is already available for the Nexus 6P and Nexus 5X - if you can't wait until the official over-the-air update arrives, and you know what you're doing, you can download the Preview from Google here.