Today Google launched Google Earth, a satellite imagery-based mapping product that combines 3D buildings and terrain with mapping capabilities, Google Search, and annotation. To use it is to enter a video game-like experience where the whole world is your play space. Considering the price (free for basic version), Google’s cachet, the richness of the data, and the snappy, intuitive user interface, Google Earth is the harbinger of a new era in which Geographic Information Systems (GIS) become a tool of the average computer user.
Complete article: Google Earth, the People's GIS.