But the really interesting part of the announcement lies in the fact that anyone can contribute their own balloon/kite imagery, effectively crowdsourcing the project. Google even outlined how to get started. With a minimal $100 investment in equipment and parts, anyone can help expand the collection.
Right now, the balloon & kite imagery is pretty limited. But historically crowds have proven eager to contribute to any project with global reach. Just look at Wikipedia and OpenStreetMap.
Google Maps has recently lost some big clients (like Wikipedia and Foursquare) after it started charging its heaviest users. These websites and many others have jumped ship to OpenStreetMap, which is a free, crowdsourced product. I hope this step toward greater openness will expand into more corners of Google Earth and Google Maps and maybe make their platform free to everyone again.