I was writing a long, long, paragraph, but it didn't really make alot of sense, instead here is my short opinion.
As Freehand says (i'd be personally have the percentage a bit higher.) - it isn't soley based on talent, but the experience and knowledge of the person who uses the said program
Take my friend for example - she can draw anything at all on paper - but as soon as you put her on a computer with a mouse or tablet, the only thing she can draw is a square, a very, very weird looking square.
Another good thing to have in mapping is patience, i've seen some AMAZING maps made by people who've spent literally a few years working on them, like nursing a baby. Of course, i've never attempted that, the longest map i've ever worked on was Urem Irnar, which spanned a few months because of lack of inspiration (Another huge thing, for me atleast.)
So, to sum it up. Alot of people have talent here - take Arsheesh, Ascension, and a few others who make satelite style maps, they don't draw them, but they do make them.
They just have talent in another way.. And patience, experience, and training - of course.