[palmer]

Windows 7 is at the very least as secure as any Apple desktop OS, if not more secure.

Depends on how you use them. If you navigate with IE (will the latest patches) to unknown websites you will eventually get zero-dayed, no doubt about it. With Safari, that is not as likely, but still possible.

[SmokingJoe]

Depends on how you use them. If you navigate with IE (will the latest patches) to unknown websites you will eventually get zero-dayed, no doubt about it. With Safari, that is not as likely, but still possible.

How so?
Given that IE 9 is more secure than Safari.
The myth of the “safe” OSX has long been destroyed:

Mac Virus Infects Over Half A Million Computer
http://thebottomline.as.ucsb.edu/2012/04/mac-virus-infects-over-half-a-million-computers

Widespread Virus Proves Macs Are No Longer Safe From Hackers

http://bits.blogs.nytimes.com/2012/04/06/widespread-computer-virus-indicates-mac-users-no-longer-safe/