When will the Microsoft office arrive?
If you mean as a native Linux application, I think never, but nobody knows. You can search or ask in the Microsoft Community for this.
you can use the Web Apps (Microsoft Online) if you want,
or you can try install MS Office in Linux through Wine or PlayOnLinux.
See relevant questions/answers on AskUbuntu.
That’s up to Microsoft, not us.
If you ask them and get a useful response, please let us know.