This amused me today from a friend of mine who noticed this. A job application on the Google website for the "Executive Assistant to the Executive Director, Google.org - San Francisco"
Check out point 3 from the mandatory job qualifications:
Proven mastery of Office applications, including Word, Excel, PowerPoint and Outlook.
The implication seems clear - if they have "interest and experience in using technology to improve work efficiency" they'll need to be Microsoft Office experts.