Any hacker who would make the first real security issue for MacOS would be the most famous hacker on the planet.
There is a genuine reason for the security of MacOS and it is not because the hackers ignore Macs.
At a Mac conference 2 years ago, someone took one of the challenges and hacked a Mac via a Firefox exploit in under an hour. I wouldn’t feel exactly safe on any platform attached to the internet.
Make that Safari, not Firefox. It’s almost a Monday.
A link:
http://www.macworld.com/article/132733/2008/03/hack.html