I'd say that the most pertinent point to the discussion is that most Mac users wouldn't have to worry about it, because spyware and viruses are not a problem in the Mac (or Linux for that matter) world.
The main reason viruses aren't a problem for Linux is it's not really a usable system.
And the main reason they aren't a problem for Mac's is hardly anybody owns a Mac.
How often to maladjusted egomaniacs attack the little guy? Oh, sure, they go after the occasional windmill but only because they think they are a giant.
Not that I'm all that happy with MS but for years they've had games and programs that run on their system.