I don't know about the viruses, but as I mentioned before, and it's a known fact, Linux & Mac both, as well as Windows, are subject to "remote code execution". That's much worse than a virus is, perhaps the worst thing that can happen to any computer user.
If the attack is successful, the one whom launched the attack can literally take over your computer. Think about that for a couple of seconds, the attacker can do pretty much what they wish with your computer. Such as stealing your data, using your computer to infect others, and on and on.
If this were to happen, and you have a recent good backup, the best thing to do is run DBAN in autonuke mode, making sure that all accessories are detached from the infected computer. Then, there are various discs for download that includes a virus cleaner, it wouldn't hurt to run that.
Then, you can use a tool such as Partition Wizard to repartition your disc, as DBAN will destroy whatever is on the hard drive, including partitions. And finally, restore your backup.
In the case of Linux, which most of their OS's or "distros" runs Firefox, the No Script add on is your best defense against this attack. It is well documented on various Linux forums. As for Apple Mac, I don't know what to advise for prevention, as I don't know what optional browsers runs on them, other than Safari.
Also, in the case of Linux, FF 3.6.4 was supposed to fix the issue, it has been a known issue since sometime in 2006. In fact, on one forum, there's a thread that's been open since that time on that subject, and I still get informed of any new answers. Hopefully, it will stop.
So to answer your question, all users of any brand of OS can be subjected to that particular attack. If you have Firefox, the No Script add on will help with Windows, too. I only allow scripts when necessary, and even then, only temporary permission is given, such as to make a purchase, pay a bill, and in some cases (such as Opera Mail) to delete unwanted mail.
I hope that my post sheds a little light on the subject. The threat of Remote Code Execution is real, and should not be taken lightly.
Cat