Office 365 is killing it because Microsoft is entrenched in enterprise. They aren't leaving any time soon, no matter what Apple, Google, Yahoo!, or any Random Startup X does.
It has less to do with the quality of the service, its ease of use, or whether or not people actually like using it than the above note about entrenchment.
It has less to do with the quality of the service, its ease of use, or whether or not people actually like using it than the above note about entrenchment.