Priceline.com just rolled out a new way to visualize locations on a map using Virtual Earth. Do a search for a hotel and under the "Area Map" tab you will see your results on a Virtual Earth map. The map includes a mini-map in the upper right hand corner for better context when zoomed close to street level. Priceline build a custom navigation and zoom bars and links to switch map style, reset the map or print the current map. The borders of the map also allow for navigating the map directionally. Priceline uses custom pushpins with rollovers containing links to additional details, a picture of the hotel, a hotel star rating and a link to the reservation system.
There are some things they could do to improve the system - dynamic result refresh when panning/zooming the map; integrate their landmark tab right onto the map so you can see landmarks in context to the hotels you're looking at and some filtering right on the map based on price and ammenities. Overall its a great start to jump in with Virtual Earth and with this foundation I expect to see some great things on this site.