In other words, this situation likely creates a significant hole in paid search referrals for eBay and in paid search ads for Google in the U.S.
Relations between eBay and Google have been strained in recent years, as Google has morphed from a partner into a partial competitor with new products like Checkout and its Google Base listings service.
In May of last year, eBay and Yahoo struck a wide-ranging partnership that, among other things, made Yahoo the exclusive provider of search and display ads within U.S. eBay sites.
Although Google performs a similar function for eBay sites outside of the U.S., the eBay-Yahoo tie up was seen as a defensive move by eBay and Yahoo against Google.
EBay doesn't have a timetable for when it might reinstate its paid search ads in Google's U.S. AdWords system, Durzy said. "We need time to evaluate the impact" of the pullout, he said. "We don't have a time for when we might turn them back on."
EBay pulled the ads "a couple of days ago," he said. "We're in the midst of an experiment and we'll see how it goes," he said.
In its official party announcement, Google clearly stated its intention to rattle eBay during its merchant conference this week.
"Are you an online seller attending eBay Live! in Boston this week? If so, join us for a celebration of user choice at the Google Checkout Freedom Party on Thursday night (6/14)," reads Google's blog posting invite.
The party will be held at the Old South Meeting House, where in 1773 mass protest meetings were held, leading to the Boston Tea Party.
Google hasn't replied to requests seeking comment.