Google is adding new product ratings into Product Listing Ads.  They are using a five-star rating system for ads appearing on Google.com and Google Shopping at google.com/shopping/

Google is implementing the ratings as they feel it will drive more traffic to Product Listing Ads and during their testing, they found it increased the CTRs.

This might also cause it where companies are reluctant to advertise with products that have no ratings, if the clicks might go to the ones with ratings instead.  However, Google has said just because an ad has ratings doesn’t mean they will always show those ratings.  It also reveals that the ratings will have a grace period that runs from late July through October 2014, when “we’ll only show ratings for products from merchants who choose to share their reviews with us”.  So merchants should take advantage of this grace period to begin sharing their review data so their ratings will continue to be displayed.

In order to give merchants time to share their review content, we’re offering a grace period from late July through October, 2014. During this grace period, we’ll allow product ratings to be shown across all Product Listing Ads where we have product review data available. After the grace period, we’ll only show ratings for products from merchants who choose to share their reviews with us.

For those who would like to enable product ratings:

If you would like to enable product ratings on your Product Listing Ads, please begin the process of submitting your review content to us by completing our product ratings form. During the initial launch, we expect high inquiry volumes and appreciate your patience as we work to address all inquiries.

Merchants will need to either share their own ratings or ratings from an approved third party aggregator.

This is currently only available to US merchants, although they plan to open it outside of the US in the coming months.