DoubleClick Enables eBay to Provide a New Service for Its Sellers Called Keywords on eBay
Although eBay is not officially a search engine (YET!), it does offer most of the functions that an engine does.
From the Press Release:
DoubleClick Inc. said on Tuesday online auctioneer eBay Inc. signed a global, multi-year pact to use its marketing tools. The Internet marketing company said in a statement eBay will use its services to improve the performance of the online auctioneer’s own online advertising programs and to manage ad serving.
The service enables eBay sellers to reach targeted buyers on eBay through ‘bid-per-click’ keyword advertising. It gives eBay a powerful way to optimize its online advertising inventory while empowering sellers to increase traffic and drive more buyers to their item listings or Store within the eBay marketplace.