Computer Crime Research News has an article where they discuss an article by major Anti-virus vendor Symantec which talks about how Mac OS X is increasing in popularity and becoming a target of hackers. This discussion is excellent for the security industry and those who would like to see more variety in the operating systems deployed on the desktop. With BSD and Mac OS X being rated as the most secure OS for either 2003 or 2004 (I forgot the link, I'll try to find it), we will now be able to see how secure it is. We will also be able to see how secure the applications that Apple has added to the BSD system are and how viable the Apple solution is compared to Linux [and Microsoft Windows].
I don't think that the vulnerabilities will ever match, or come close to matching what we have seen with Microsoft products. The reasoning for this is that Microsoft has been in the spotlight for many years as the front-runner, while the other boys have stood by the way-side learning and moving in a more secure fashion while learing from the mistakes and successes of Microsoft. It is much better to have options when deploying a server or desktop, so I welcome the competition of Microsoft, Apple, and any other OS vendor. I do like to preach about open-standards though, and the consumer should not have to be the one struggling to implement a solution because the vendor has gone out of their way to prevent interoperability (read Microsoft).