Google is re-investing the revenues they get from ads on projects to improve our world. Following google.org initiatives (RE<C, RechargeIT and others) Google is now calling for ideas from outside to make them happen in Project 10 to the 100.
Googlers are brilliant people and you can notice that from the great products they bring to market.
Still the major innovation of Google is their business model. Most of what google does is free for the user: Gmail, Docs, Picasa, Earth, Maps, etc. They are masters of the economics of free, and this is yet another great value for the user. At the end, Google is changing our world, and we do not need to pay for it.