It’s just one of those things that the media hungry –but security disinterested– public has turned into an axiom.
But now that OS X is garnering an increased share of the operating system market, it is increasing its value as a platform for malware, and consequently increasing in value in the software security market.

www.betanews.com/article/Macs-dont-get-viruses-myth-dissolves-before-publics-eyes/1251493625