http://gizmodo.com/373109/who-will-get-hacked-first-vista-osx-or-linux-place-your-bets-here
pwned! Mac OSX hacked in under 2 mins, and everyone always raves about the security of their Macs..
Seriously though, I was surprised. I expected it to go Vista, OSX, Linux. But apparantly people claim that OSX is less secure since they haven't been in the public eye, not nearly as many attacks against macs as against Vista. Linux is so secure because its open source, that makes sense. Surprising though, but makes sense when you think about it.