One thing that I don't get about this contest is that they included Chrome and not Opera.
Yes chrome is the "new kid in the block" but the other one, despite it's low market penetration, has been around for many many years.
(PS: I am an Opera user, but not a fanatic/fanboy etc. I am not trying to start a browser flame here.)
http://www.matasano.com/log/644/safety-vs-security-2/
OS X is a suburb. Win32 is downtown Manhattan. You might prefer the suburbs, but remember: neighborhoods change.