Live labs has just released "3d mode" for local.live.com. I've tested it on IE7 and it's like Google Earth mapped with local.live.com data.
Here's what it looks like if you haven't installed it yet:
Once you click the install button in the left sidebar, you get a helper program to install locally, which augments the local.live interface whenever you visit the site.
Here it is installed on Vista in IE7:
