I also liked the "for Office, much of the work for a Linux version has already been done in creating the Apple Macintosh OS X (Unix) version".

This couldn't be more false. Sure, it runs on a Unix OS, but it's tied to the Carbon API, aka an Apple specific API that was made to bring OS 9 and older apps into OS X with minor work. To make a Linux version of Office, MS would probably be better off starting from scratch then converting the Mac version of Office.