You could get a Mini Mac for a reasonable price - you'll love it!
If the people who start these stories knew a bit more they would know that when you download a file in OS X it detects if it's an application and warns you. You have to accept the file at this stage (no matter what they called it).
You then have to launch the file to load it - you will be asked to authenticate the application and need to use the administrator password.
I didn't open this can of worms, I don't think there's any mileage in the 'PC are better than Macs' mentality.
The 'smug' comment in the BBC, and other stories, has only one purpose, as far as I can see.
P.S. Despite these stories - anyone know of a Mac that has been infected?