Netragard’s CTO was quoted in the following article titled “2007: How was it for Apple”. Here’s the article and here’s the quote:

Adriel Desautels, chief technology officer for security company Netragard and founder of the SNOSoft research team, said: “If OS X had the same installed base as Windows, Linux and other systems, it would be less secure or at the very most, as secure as the other systems … It’s just a matter of what
[attackers] focus on.”