Google begin testing a new feature of AdWords called “AdWords Comparison Ads,” which lets users compare multiple, relevant offers more easily. Comparison Ads improves ad experience on Google.com by letting users specify exactly what they’re looking for and helping them quickly compare relevant offers side by side. With Comparison Ads, you can also target your offers at a more granular level, leading to more valuable, qualified leads. Comparison Ads is focused on a number of ways to enhance user experience: • Speed -- Comparison Ads shows targeted offers in less than a second • Transparency -- Comparison Ads only shows real products • Privacy -- Comparison Ads won't send advertisers any user information, including anonymized phone numbers, unless user explicitly requests more information about an advertiser's offer.
Full Article: AdWords blog