The National Geographic has their new Map Machine web mapping service up and online. Since it’s put together by ESRI, it’s a safe bet they used some combination of ArcIMS 9.2 and ArcServer 9.2. I think this map interface is one of the best I’ve ever seen for publicly digestible online maps. They’ve added all sorts of little innovations that make life simpler. My personal favorite is the zoom bar. Rather than the vague “1,2,3…16” classification of zoom levels, they’ve used a much more intuitive “continent, country, county, city, street” classification system. Be sure to also check out the theme viewer at the top!