Hmmm. Ya, my 1st thought too was the choices, followed by "Please no flame wars", then of course come the flames.. aargh.. lol
I don't think useful poll results is Lasher's intent. He said he was curious what fellow members are running.
Ah, well.. Hey, I like Windows at home, for my hobbies and online presence, and in my day gigs have been a command-line Unix guy for a lot longer (since the 80's). For their GUI, Solaris and Linux suck. For graphics and software availability, they suck. As servers, they're top notch. So, there are pros and cons to all, depending on you, usage, applications, etc.
So far, it doesn't seem that there will ever be the quality and availability of software for Linux that we have for Windows, when it comes to desktop usage for the masses. For that matter, the Mac has less available, but is very stable for people who just want basic stuff and don't want to worry about doing any administration.
As far as viruses and spyware are concerned, one must be vigilant. It's not because you have one OS or another, it's because there are assholes who think it's cool to write such crap. Any careless person can have their system affected.
We're well beyond the "IBM PC" age, so if we're talking about personal computers, it's accurate to say that a Mac is a PC. The marketing war is really between MS Windows and Apple Mac OS, not between PC and Mac. A Mac IS a PC.