It allows you to see the links between countries easily. So, once you've created your XML and map, and just want to debug it, you can just pop them in there, and you'll be able to see if you've made all your connections correctly.
Hope it's useful to some of you map makers!
Notes: I only own Flash MX 2004, so it currently only imports jpegs at the moment. I'll export it to Flash 8 so it can loads pngs & gifs when I'm in work in teh next few days. In the mean time, if you want to use it, then just upload a jpeg for testing purposes.