No matter how you slice it, Amazon.com is currently dominating the retail space. In fact, Amazon accounted for almost 50 percent of all e-commerce sales last year. As a result, retailers should be doing all they can to take advantage of every possible opportunity to find success. One way they’re doing this is by leveraging Google Shopping ads known as Product Listing Ads (PLAs), which have quickly become the most popular ad format for retailers. These ads are so popular that their spend has far eclipsed that of text ads.