Last week Flickr announced a great set of enhancements to their service: geotagging of photos on a map. Once again they've done a nice job in the interface by making it really, really easy. Drag-n-drop them on the map and you're done.
When it comes to map mashups there's no doubt that Google Maps leads the way. On ProgrammableWeb we list 1,964 Google Maps mashups, almost four times as many as any other API. This popularity makes utilities built on top of Google Maps especially interesting, such as this contextual menu control, which pops up a menu when the user right clicks.