We are using a plugin called MapPress that can add maps to your blogs or posts. There’s a good deal of documentation on how to use it, but you can add maps with multiple points of interest, or import KML files or a tour built in Google Earth; an example might be to show the route of the Odyssey. Sample Google Earth tours can be found at Google Lit Trips, among other sites; sample KML files can be found on the web, though sometimes you need to validate the KML files to insert them into the MapPress map.
Additionally, you can do mashups, or make one map from a combination of multiple maps used throughout your blog, for a specific tag or category. An example is a mashup of all the trees on the Reed campus.