Isn’t amazing that an unpatched Linux deployment survives being rooted for at least 3 months compared to minutes a Windows XP SP2 – which according to Microsoft is their top of the line OS!
While this study is careful to say that because of the increased deployment and piracy of Windows in developing countries (#4 in the Reasons section), there could be greater threats to Win32 systems than against Linux.
A lof of the threat to Linux is mitigated because of the security model that it is built on, harnessing the 30-odd years of the Unix tradition. In fact, I would say that with the impending increase in deployment of SELinux, threats and exploits against Linux will decrease significantly. I hope the Honeynet Research Alliance will do a similar study in 12-18 months.