Google\'s free \'product search\' would soon be a paid service in the US under which merchants and retailers will have to pay for listings of products. \"We are starting to transition Google Product Search in the US to a purely commercial model built on Product Listing Ads. This new product discovery experience will be called Google Shopping and the transition will be complete this fall,\" Google Shopping Vice President (Product Management) Sameer Samat said in his blog on Thursday. The new initiative seen as a step to boost company\'s revenue will in addition provide the customers a higher quality shopping experience. \"shoppers can easily research purchases, compare different products, their features and prices, and then connect directly with merchants to make their purchase,\" Samat said. The service will be based on bid price and relevance giving the merchants and retailers a greater control over where their products appear on Google Shopping. Over a period of time they will also have the opportunity to market special offers. The internet company has begun experimenting with some new commercial formats on Google.com that will make it easier for users to find and compare different products. These include larger product images that give shoppers a better sense of what is available and also the ability to refine a search by brand or product type. These new formats would be labeled \"sponsored\", and take space currently occupied by AdWords. Users maybe able to view details regarding a product in one place and make a decision on the product and merchant of their choice. \"Google Shopping will empower businesses of all sizes to compete effectively and it will help shoppers turn their intentions into actions lightning fast. The changes are a first step toward providing technology, tools and traffic to help power the retail ecosystem,\" Sampat said.