Apple Mac Vulnerability and Mac OS X antivirus
I don't think anyone can deny that Apple makes some great computers. They definitely are on the cutting edge of design and user functionality. However, the company wants you to believe that the operating system is inherently secure against worms etc. Well I offer the counter argument that the software is significantly behind Windows Vista and Windows 7 in security. Why, because Apple simply hasn't had the market share to be cost effective for viruses writers. If you are a virus maker, you'll want to get the most bang for your buck effort. Consider Macs market share in previous years amounting to 3 or 4% of the PC market. Now, according to the Sydney Herald, Macs / OS X have around 10% of the market making it a more juicy target to attack.
The next problem is Apples security response capability. Since they haven't previously had many viruses, I argue that the company will not be properly prepared to deal with a large and emerging threat. On the contrary, Microsoft, given all of the bad publicity, has invested massive amount of cash into security research and detection. You can read the security response teams blog here. The counter argument would be that Microsoft software is inherently unsecure so they have to release regular patches. However, given the nature of software if someone wants to find a security exploit they will. And in Apple's case, the virus or trojan could go undetected for weeks. Some of the latest Windows antivirus has heuristic analysis and an opportunity to send in suspicious files (Sophos/Cyberdefender)
There are also few Mac Os X antivirus solutions. Conversely, Windows has a huge following of antivirus products with a constant vigilance towards the latest threat. Windows users are also more a privy to the fact that their computer can be hacked and even expect it.
Finally, Mac's run on the x86 computer architecture (the same intel chips are in Macs as PC's) and therefore are a lot more similar and unsecure than meets the eye.
As explained above if you have a Mac, I would recommend you that you download an antivirus solution. In fact, there is a free antivirus solution called ClamAV. Unfortunately, the software is dependent on community involvement to discover viruses and lacks auto protect. If you want a large company's antivirus with definition and auto protect, you'll have to use Symantec Norton Antivirus 11 for Mac OS X. Unfortunately the software isn't free and you'll have to shell out 49.99 for the software. However, you will get auto protect technology and specific technology to protect against software vulnerabilities.