Here's more on what appears to be an AJAX-style mapping application by Microsoft, ala Google. - http://virtualearth.msn.com/
They also have a blog site up, tracking the development of the Virtual Earth project.
One of the things I also notice here is a reference to the project involving determining a location via WiFi. I'm not entirely sure how this works, perhaps it is through public hotspots, doing a resection using signal strength or some other attribute of the WiFi signal, akin to how GPS does resections using signal code timings.