According to Sophos security, the whole world should switch to macs to get rid of the security problems. This would be great for business! Currently I do not order with companies who put up Word or Excel formatted price lists, simply because I can’t (and to some extent refuse) open them.
In the long run however, this would shift the security problem to the Mac side of the world. Why do Microsoft machines get attacked so often? Simple: because their user base is large, which means there are more Microsoft (black hat) hackers out there. Additionally, the targeted audience is large in numbers. When the whole world uses Macs, the black hat hackers will turn to OSX as target.
But then again, the security model of OSX is (luckaly) a lot better than that of a Windows machine so the damage done largely depends on how the system is secured by the user. At least on a Mac you have the means of securing stuff properly.