Yeah, i just read this article. It does seem as if the hacking world will try at taking hits at OS X, but i don't think that it will be as easy as what the article makes it out to be. Unix is known for being one of the best OS's for security, like stated in the article, this is why thousands of Servers for networking the internet use Unix.
However, i am not saying it can't happen, i just think it will be difficult, let alone ridiculous because of Apple's small [6.3% i think] market share.
The article makes some valid points. Part of the reason security is so good on MACs right now is because of the simple fact that PCs have a much higher market share and therefore there is more info in the hacking community about how to get into these machines. As time goes on and there are more MACs in more households across the globe, I'm sure you will start to see more attacks and more viruses. I do believe though that OSX has a secure foundation behind it and that it will NEVER be as bad as WINDOWS in terms of security.