As more and more consumers use their phones for both business and product search and purchasing, mobile ad formats for retailers are becoming a more compelling way to connect with these users. Today, Google is bringing its seller ratings ad format to the mobile platform, allowing searchers using Google on the mobile web to see ratings of merchants within a search ad. Another interesting tidbit from the post—Google Mobile searches were up 130 percent year-over-year in Q3 of 2010.

Similar to seller ratings for web-based search ads, the mobile format allows advertisers to include a rating for a business. Seller Ratings are aggregated from merchant review sites and Google says the the extension will only show when a merchant’s online store has a rating of four or more stars and includes at least 30 reviews.

The ad itself shows the merchants star rating and posts a link to the seller’s reviews. Google says that the mobile ad formats with seller ratings are only available on Google.com, Google.co.uk and Google.de domains. And Google cautions that these types of ads are only appropriate for “advertisers who provide users with paid goods or services or those that enable the buying or selling of products or services via a marketplace.”

It’s not surprising that Google is continuing to ramp up its efforts in mobile search offerings. Google already does pretty well in terms of mobile revenue (in the company’s last earnings call, the search giant said that mobile search is on track to be a $1 billion business in 2010). In the call, Google SVP of Product Management Jonathan Rosenberg said that mobile search queries have grown five times over the past couple of years.