Last week we started telling you about the new ArcGIS Online World Topographic Map. As I was working on the design of that map, with the intent of providing a better basis for mash-ups, I had an idea. It was born of frustration with the fact some mash-ups don't work because too much information obscures the base map, making for an unreadable, often ugly result. Demographic layers represent a great example of the kind of information that just doesn't always work well in a simple mash-up. Read More...