"how would they earn there money?" I think that endgame is obvious, they bribe users to let them track them. Information about TV and radio habits is very luc

"how would they earn there money?" I think that endgame is obvious, they bribe users to let them track them. Information about TV and radio habits is very lucrative for companies like Nielson -- they pay quite well for participation and diary keeping. Even taking short surveys over the phone is rewarded with $25-50+ checks. A company like Google is in a unique position to automate this process -- opt in to tracking and receive a tiny percentage of the more lucrative ads google is able to get. Win-win, tell your friends and almost everyone signs up.