You can't compare Apples and Oranges (Windows)
Well, there are plenty of people who don’t agree there.
Microsoft for one compare their security to Mac and Linux on the basis of vulnerability counts:
http://www.microsoft.com/technet/community/columns/secmgmt/sm1007.mspx
The Linux and Mac advocates concentrate on system architecture:
http://blogs.zdnet.com/threatchaos/?p=311
http://www.commercialventvac.com/~jeffs/WindowsVsLinuxSecurity.html
Exactly which side is right is up for discussion.
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