In Google Merchant Center added Product Ratings section
Adding this section is designed to assist sellers to quickly solve problems of this kind. Google notes that among the most common shortcomings is the lack of dates, text, or author's opinion. Diagnostic data will be available within a few hours after a feed upload.
Previosly in November 2016 in Russia has earned the Google Customer Reviews. From the users ratings calculate seller rating, which is then displayed in the search ads and Google Shopping.
The program Product Reviews in Russia is not yet launched. The products raing appear on Google Shopping in all countries where this service.