For home users, yes. But in the business world, it's the Microsoft Office Suite, especially Outlook + Exchange. Sure, MS Office has been ported to OSX, but it's more expensive to go with Apple Hardware than commodity PC + MS Windows.
If Microsoft flipped their lid and ported Office to run on common Linux distributions (Debian/Fedora), you'd see a lot more corporations switching.
Microsoft does have their Office365.com, which is a web-based version of Office. I haven't tried it myself, but from what I've heard, a lot of its advanced features rely on Silverlight and using browsers other than IE on Linux or Mac OSX puts you in a sort of basic mode. The advanced mode is very comparable to running the desktop version while the basic mode is akin to the Google Docs editor.
If Microsoft flipped their lid and ported Office to run on common Linux distributions (Debian/Fedora), you'd see a lot more corporations switching.
Microsoft does have their Office365.com, which is a web-based version of Office. I haven't tried it myself, but from what I've heard, a lot of its advanced features rely on Silverlight and using browsers other than IE on Linux or Mac OSX puts you in a sort of basic mode. The advanced mode is very comparable to running the desktop version while the basic mode is akin to the Google Docs editor.