I uploaded a movie of playing Google Earth newest version with my mushup contents "Train Mapping" (Japanese Only).
We can come and go very smoothly between "Macro<--->Micro". I had tried the mashup of Google Earth and Second Life (Japanse article) before, But This sense is quite different from it.
The interface that can shuttle freely from "Maximum" to "Minimum", or from "Far point" to "Neer Point" is very comfortable and impressive. This is a reason why people are strongly attracted to the map software such as Google Earth - It is not in present Second Life.
We should make the interface that draws out a body sensation different from the real world more strongly. The interface of Google Earth will become a hint for that.