The big reason to stop coloring maps

Hey Wyoming, did you know more people live within my borders than in yours?  Really DC, but I'm so large and colorful.  Wyoming is much larger than DC!

From Let’s Tesselate: Hexagons For Tile Grid Maps by Danny DeBelius of the npr visuals team:

As the saying goes, nothing is certain in this life but death, taxes and requests for geographic data to be represented on a map.

For area data, the choropleth map is a tried and true visualization technique, but not without significant dangers depending on the nature of the data and map areas represented. Clarity of mapped state-level data, for instance, is frequently complicated by the reality that most states in the western U.S. carry far more visual weight than the northeastern states.