You just made George Ou's head explode
Tom Yager makes a practical comparison between the relative security of Windows and OS X as servers.
So, after all this, do I have enough to judge Windows inherently more vulnerable to severe malware than OS X? I do.
As a desktop OS, one point you could make against OS X is that “just losing your user data” can still be rather devastating, but Yager’s list is a great compilation.
UPDATE: Whoops! The Macalope thought he had gotten this link from the RSS feed of Yager’s blog but he had actually gotting it from Mr. Gruber and he didn’t notice it’s from back in August. Still an interesting read and one the Macalope had failed to take note of at the time. Probably because he wasn’t blogging then.