Ok, first off there were a reported 640,000 infected Macs - not millions.
Secondly, this was a "Flashback Trojan", not a virus.
Thirdly, this was due to an exploit in an older version of Java (not Adobe this time!!) that has been patched. However, some users are simply not chosing to update their OS, thus remain susceptable to these kinds of things.
If you don't patch your machine, and you are running 3rd party extensions on your OS ... you are going to be vulnerable to an exploit.
They don’t listen this is about the 90th time this so called “virus” post has been posted and every time they are told it isn’t a virus but they see the headline and don’t read anything more.It so far has done little to anyone, it has to be downloaded and opened by the user and by now I’d hope everyone had got the update that was offered 2 weeks ago to keep this from happening.