Nielsen survey: Most people trust online product reviews

"The explosion in consumer-generated media over the last couple of years -- we are now tracking over 100 million CGM sources -- means consumers' reliance on word of mouth in the decision-making process, either from people they know or online consumers they don't, has increased significantly," said Jonathan Carson, president of online, international at The Nielsen Company.

He added: "However, we see that all forms of advertiser-led advertising, except ads in newspapers, have also experienced increases in levels of trust, and it's possible that the CGM revolution has forced advertisers to use a more realistic form of messaging that is grounded in the experience of consumers rather than the lofty ideals of the advertisers."

Brand sponsorships have enjoyed the greatest surge in consumer trust since that element was added to the survey two years ago, surging 15 points to its current level of 64 percent.