In my world (I'm a principal security architect for Microsoft), this is no big surprise. Macs have always been far more vulnerable to hacker assaults than Windows computers, by almost every metric that means anything. Yes, Macs do have far more software vulnerabilities than Windows computers. If you don't believe me, go to any vulnerability database (I like Secunia's advisory database) and compare any operating system or application from Apple and Microsoft, head to head, over the same time period during the last five years. Most people are absolutely shocked to see that Microsoft software in general, and Windows in particular, has suffered far fewer vulnerabilities than Apple software and Mac OS X.
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