An article at the Register claims that Linux and Mac OS X would still be more secure than MS Windows even if they were used more frequently. Its a good article for pondering.

One issue I have with the article is the author's claim of a security risk created by Microsoft's monoculture. The author argues that Windows users are exploited because they mainly only use Outlook (which uses the unsecure Internet Explorer), whereas Linux and OS X users have a plethora of apps to use. If we lived in a Mac OS X world, however, there would have to be one killer Outlook-esk OS X app that businesses would flock to -- thus creating a target for virus writers due to popularity. It might be harder to write exploit code for a Linux/OS X app, but it can be done.

Also, the author states that some Linux servers are unsecure by holding MS-type documents (Word .doc's, Excel .xls's). From what information I've seen, macro viruses have gone the way of the dinosaur the last 2-3 years. Word/Excel viruses don't proprogate quickly and efficiently like the viruses/worms of today.

I agree with the author that if we lived in this mythical OS X/Linux world, there would be less viruses floating around. Most of us can agree that Microsoft Windows products are not the most secure in the world. But there's a fine line between comparing the number of flaws between OS's and straight-up Microsoft bashing.