Re: OK so let me get this straight.
NO intelligent user of ANY OS supposes it to be "magically" completely secure (the ones who do don't count).
Don't be ridiculous. Of course they count. And some of them (at least one whom I personally know) are quite intelligent.
Unix systems are not magically "secure" but they are demonstrably "more secure".
Their use across the web does not constitute a "small target".
As far as user-targeting malware is concerned, yes it does. Servers are another matter, but servers are much harder to infect than desktops to begin with. For starters, they almost never hang out in sleazy websites like users do.
Let's say it yet, yet, yet again: There are currently no viruses proper - at all - for OSX (there will be, sometime, but this isn't one of them).
You do realize that even Apple stopped trying to push that particular line of bull 5 years ago, right? Yes, OSX viruses do exist and are in the wild and have been around since at least 2006. For a few examples, see
OSX_IWORM.A OSX_SLORDU.A OSX_MACKONTROL.A and OSX_MUSMINIM.A all of which are viruses that can be picked up via drive-by-downloads. And those are just a few examples. Yes, there is much less malware of all types around for OSX, but don't be one of those fools going around believing it doesn't exist.
OSX (and anything else *nix based) is harder to infect that Windows, but by no means is it so difficult as to not be worth it were there a greater number of potential targets. The diminutive market share of non-Windows PCs is very much one of the reasons we don't see more non-Windows malware.