Have you explored Google Earth recently? I have a hard time leaving a browser for other applications, but it is getting more compelling. Take a look at this view of Salt Lake City.
Those green dots are real-time traffic points communicating current freeway speeds. You also have temperature reports in real-time from around the city. The blue dots are images. You can add an incredible amount of other data, even YouTube videos or Twitter posts from locations around the city. Another layer will pull up relevent Wikipedia information found on the 3-D map. There are innumerable additional layers such as NY Times and Google News that associate any news from those sources with points on the map. I met with some people from the Center for Active Sensing and Imaging at USU this morning who have a new LIDAR system for 3-D imaging that will automate the creation of 3-D aerial and ground imagery, doing some very cool stuff that will contribute to the full enablement of the 3-D virtual world. This is one of the new USTAR teams that you will find on innovationutah.com.
Now, take a look at Monster Milk Truck. Google lets you drive the truck anywhere you want to go in the terrain. It won't be long before your avatar will be able to wander the virtual earth at will. Then, we can integrate key functions between the real and virtual worlds, letting your avatar control specific real world functionality. How about that?