Adam and I spent time with some great folks at ORD Camp (a conference very much in the style of Foo Camp but strictly for us midwest geeks). We got to see some of the work of Dennis McClendon of Chicago CartoGraphics.
Dennis makes some seriously cool maps. The below were done for a book parents would read to their toddlers. Here's one of Chicago:
And one of Washington, DC:
For these stylized maps, Dennis mentioned that he is of an old school camp of cartographers that start with nothing. A blank sheet of paper. Then he adds to his design until the most minimal and necessary elements are there.
He mentioned an alternative and fairly popular approach is to take a large or "larger" data set of map features and stuff , and then proceed to subtract things from it until you feel only the necessary things remain.
We saw some of those maps that start with a lot and try to go to a little versus his maps that start with nothing. His approach of addition is better.