There are more than viruses with which to contend: worms, trojans,
denial of service, etc. Reading the descriptions reveals there are
potentially a lot of holes still in Linux for various exploits which
would not be considered a virus by common definition.

For those using FireFox, how many have updated to 2.0.0.17 yet? These
items were fixed in 2.0.0.17 released September 23, 2008:

XBM image uninitialized memory reading
resource: traversal vulnerabilities
BOM characters stripped from JavaScript before execution
Crashes with evidence of memory corruption (rv:1.9.0.2/1.8.1.17)
Privilege escalation via XPCnativeWrapper pollution
Forced mouse drag
Privilege escalation using feed preview page and XSS flaw
nsXMLDocument::OnChannelRedirect() same-origin violation
UTF-8 URL stack buffer overflow

Notice the privilege escalations. That's why I self-install any
critical (to me) apps and don't wait for the repos to be updated.
Even my 6-year-old Red Hat 9 is presently running 2.0.0.17 though
there's no support from RH for that release anymore.

> And perhaps those problems did exist. But it is a real easy
> fix when dealing with Linux, simply rebuild your profile and the
> virus is gone.

I don't follow what you mean by "rebuild your profile". Would you
please clarify?

> In Windows you may have to go to lengths such as reformatting
> to get rid of a virus, and even that is not a guaranteed fix.

Very true if reformatting with MS tools esp. on XP and earlier.
Look back to Roy's recent article about his wife's XP system.
I had to get a thorough low-level formatter to help a friend
with his XP system that was similarly infected. Yet in all
these years with Win95, 98, 98SE, NT, Win2K, XP, and now Vista
I've never had any infection whatsoever on any of my desktops
or laptops and my laptops have been jacked-in to scores of
client's networks and I heavily browse the web. Go figure, and
I'm presently running Win2K-SP4, WinXP-SP3 and Vista-SP1.