Google launches its payments and certifications service, GBuy, June 28. The "PayPal killer" service, which has been quietly tested by online retailers since early 2005, will process orders on the Google domain, and then hand consumers back to the requesting site once the transaction is complete. During the transaction, Google will capture e-commerce data, which will help drive ever-more-precise targeting in future searches.

On the search results pages, Google will designate qualifying merchants with an icon indicating they are "Trusted GBuy Merchants." Analysts suggest this stamp of Google approval will encourage consumers to patronize those merchants deemed GBuy-worthy. Great for consumers and merchants alike? Maybe. Merchants may fear that Google capturing transaction data may lead to the company charging steeper prices for sponsored links, even if the merchants benefit from the GBuy seal by drawing greater numbers of customers.

During the beta phase of GBuy, Google will not charge merchants for the payment service; it's expected the company will charge 1.5% to 2% down the road, according to speculation in a Forbes.com article.

One wonders if eBay -- owner of rival PayPal -- will accept GBuy-administered transactions! PayPal prez Jeff Jordan commented to the WSJ.com: "It's a very legitimate competitive threat. It's hard not to pay attention to what Google is doing." PayPal, which is responsible for nearly a quarter of eBay's $1.3 billion quarterly revenue, commands a 24% market share of U.S. online payments, according to the same article.