Jonathen Hawk has published a great article on ATLAS and creating a mashup with Virtual Earth. I really can't wait to get my hands dirty with ATLAS and get it into my pet site to benefit the community and hopefully pump up some promotion of the site!
Australia is still not mapped on VirtualEarth except a few main suburb names, GoogleMaps only has an outline! The USA/UK is mapped on both. VirtualEarth also has some of Europe mapped too.