Microsoft has made Office 2016 for Mac available to their Office 365 subscribers so if interested you would log into your online account and see if it’s available. If you wish to purchase outright by not subscribing to Office 365 you will have to wait until September.
On my account I currently only have access to Outlook 2016 (as I only have OSX 10.9.5 on my test Mac and you need 10.10 for the full Office 2016) which I have installed and currently putting it through the paces. At first glance it’s looking more like Outlook 2013 for Windows which is a good thing for me as it will hopefully be easier to switch between the two OS’s with more ease.
Here’s a couple of screenshot:
For more information please see the Microsoft blog here: https://blogs.office.com/2015/07/09/office-2016-for-mac-is-here/