Personally I can't see it getting many people to switch. A regular person is gonna go "So what, my PC already shows my digicam photos. Why do I need a Mac?"

The virus one is pure scaremongering - if people use regularly updated Anti-Virus, it's unlikely you'll ever be on the wrong end of a virus. Far more of a threat IMO are phishing attacks which affect PC's, Mac and anything else with a webbrowser.