You may remember that the Pwn2Own competition was run recently, designed to reveal hidden security flaws within browsers and operating systems. Charlie Miller, who was one of the competitors in the competition, has come out with a rather controversial statement: Mac OS is theoretically safer than PCs.
In an interview with Tom"s Hardware, Miller stated, "I"d say that Macs are less secure for the reasons we"ve discussed here (lack of anti-exploitation technologies) but are more safe because there simply isn"t much malware out there. For now, I"d still recommend Macs for typical users as the odds of something targeting them are so low that they might go years without seeing any malware, even though if an attacker cared to target them it would be easier for them."
He has also said that whatever you do, keep your system up to date, and be 100% sure you know what you"re doing. The reason for this is because no anti-malware protection would have stopped him; "None of those protections would have probably worked, or at least there were potential workarounds. The best thing the user could have done is not click on the malicious link. Of course, in some cases such as a man-in-the-middle attack, even this wouldn"t have helped."
So, to summarize, Miller says that Macs are less secure in terms of technologies, but there just aren"t the threats out there to make users worried.