Google AdWords are appealing to many businesses, but they’re perhaps most appealing to businesses selling products online. After all, every click on an AdWords ad could lead to an immediate sale.

For that reason, it’s no surprise that many online retailers use AdWords on a large scale.

A year ago, Google announced the beta of a new AdWords offering, Product Listing Ads. The goal: make it easier for advertisers selling physical products to effectively reach potential buyers using AdWords.

These ads, which appear alongside standard AdWords ads for select search queries, work in conjunction with advertiser Google Merchant Center accounts, and display product-specific data, including price and a photograph.

According to Google, Product Listing Ads have been a rousing success; “we found that people are twice as likely to click on a Product Listing Ad as they are to click on a standard text ad in
the same location
,” the company revealed yesterday. Which is one of the reasons Google is expanding the availability of Product Listing Ads.

Within the next week, all AdWords advertisers in the United States will have the ability to use Product Listing Ads. For advertisers with lots of products, the good news is that, unlike Google’s similar Product Extensions offering, no keywords or ad copy is required. As Google explains, “Product Listing Ads are automatically triggered whenever someone’s search
matches an item in your Merchant Center account, making it easy to show relevant
ads for your entire product inventory.

According to Search Engine Land, Google is allowing large advertisers with managed advertiser accounts to bid for Product Listing Ads on a CPA basis; everyone else bids using the standard PPC model.

Needless to say, Product Listing Ads could be a boon for retailers of all shapes and sizes. The truth is that as effective as AdWords are generally, as search evolves, so too will search advertising. As we’ve seen, search engines, including Google, are working to refine how search results within particular verticals are displayed. And it makes sense that search ads would follow a similar evolutionary path. When it comes to advertising physical products in search, it’s really no surprise that ads containing a price and photo would do better.

Of course, retailers using these ads will need to be laser-focused on conversions. After all, while it’s great that Google has seen Product Listing Ads generate twice as many clicks as standard AdWords ads, advertisers who haven’t done everything possible to maximize conversions could lose out as increased clicks boost their search advertising costs but not sales.