Well, 2 things:

* There are, right now, online browser-based versions of most of their office applications available, which work fine on Linux.

* if [1] is anything to go by, we might see client-side Javascript/Electron based clients, which would make the porting to other platforms a lot cheaper/easier to maintain. Even if a "native" (read: electron-wrapped) Linux client wouldn't be in the works, the browser-based versions will probably be just the exact same version.

[1] https://twitter.com/TheLarkInn/status/1006746626617008128