In short there is nothing they can do any better. They work fairly differently. Others would argue they are easier to use etc, however no system however easy it is to use on any scale is going to be as easy to use as the system you are already happy with. You miss out on a few bits of nice software, but really, nothing there isn't an application for in Windows which works just as well. I will admit you don't have to think about viruses etc anywhere near as much (if at all) as others have pointed out. This may or may not change any time soon. Although if your happy with your Windows set-up (personally i have never had a virus issue) then why change.
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Anyone who isn't confused really doesn't understand the situation
http://craigk.org/pictures/
Can you work out the code?