IEEE Spectrum has an article about a presentation that they called The most disturbing presentation of the year. Games designer Jesse Schell describes at DICE 2010 a future where everything we do is motivated by getting game points--we'll be living in one big game.
Although he describes the future, I think parts of that future are already here today. Think frequent flyer miles and loyalty points. As with any technology, this can be used for good or for evil.
Then again, isn't life already motivated by potential rewards? It is just that in real life the rewards are not as obvious or measurable as simple game points. Some rewards come many years after our actions. Some rewards come from persistence and dedication. Some rewards don't make sense to other people. If you think of your current life as a game, what game points do you value?