Are consumers really controlling demand and hence decide on what is happening in business life? A lot of people will argue with that theoretical (some will even call it naive) idea.
Instead of wasting time on this rhetorical question, the guys of CarrotMob are trying it out. By uniting a lot of consumers who care about sustainability and then letting business compete on their mutual investment, they may really give power back to the consumer.
Check it out at http://carrotmob.org.