http://www.theregister.co.uk/2008/12/02 ... av_advice/
For the first time, Apple is recommending the use of anti-virus tools to protect Mac systems.
Long something of a phantom menace, strains of malware capable of infecting Mac machines have gradually been increasing in prevalence over recent months. In addition, VXers are making more use of web-based attack and applications specific vulnerabilities to infect PCs whatever their underlying operating system might be.
Windows-specific malware attacks are still orders of magnitude greater than assaults on Mac machines, but the risk to Apple fans is now enough for the Church of Jobs to admit a risk exists.