For the longest time, Google has been the synonym for free, at least as far as regular users were concerned. Likewise, any site could reasonably expect to be included in the search results, providing Google deemed it relevant enough. The only people who paid were those that wanted to promote their sites on Google via search ads and later via the ad network.
But that is changing, Google is migrating from a free product search engine to a paid model, i.e. shopping sites will have to pay to be included.
Google Product Search, which has been around for a decade, even though it didn't always have this name, is dead to be replaced with Google Shopping.
But, unlike Product Search that was a specialized search engine, Google Shopping is an advertising platform, one that looks and feels like search, but is not.
The model is simple, companies will pay to have their products included in Google Shopping. When a user searches for something related to those products, a Shopping box will show up, under a "sponsored" label, displaying details about relevant products, but only from those that paid.
"We believe that having a commercial relationship with merchants will encourage them to keep their product information fresh and up to date. Higher quality data—whether it’s accurate prices, the latest offers or product availability—should mean better shopping results for users, which in turn should create higher quality traffic for merchants," Google explains
The transition to Google Shopping will be complete by fall, but Google hasn't given a specific deadline. This only covers Product Search in the US, the feature will continue to work as is elsewhere, for now.
"Ranking in Google Shopping, when the full transition is complete this fall, will be based on a combination of relevance and bid price--just like Product Listing Ads today. This will give merchants greater control over where their products appear on Google Shopping," Google added.