The answer is "It depends"
What it depends upon is your Office 365 subscription level.
Yes - Office 2016 was released yesterday but it has not arrived for all users under Office 365.
I have been watching discussions across social media in the last 24 hours and a lot of users are asking when they will receive their upgrade to Office 2016 on their Office 365 subscription.
In that FAQ there is a chart, displayed below, which shows when different Office 365 subscription plans will see the Office 2016 versions of the Office programs.
As you can see those plans on Current Branch have access to Office 2016 for new installs immediately while the Office 365 ProPlus plans for Enterprise, Midsize and Education should see the upgrade early next year because they are on the Current Branch for Business.
The idea behind these branches for updates run along similar update branches for Windows 10 and is intended to maintain stability for those users who depend on line of business applications and other functionality.
The First Release option is available for any user or organization under the Current Branch for Business that wants to gain immediate access to the latest versions of the Office 2016 programs. An admin for those organizations can designate individuals or the entire user base to receive early access to the updated programs for testing and/or daily use.
Although not many individuals will have Office 365 Enterprise plans there are some who have purchased them and may need to use this option to gain immediate access to Office 2016.
Those users who subscribe to consumer versions of Office 365 should have immediate access to the Office 2016 update although it is a staged roll out so that may impact the delivery timeline.