EBay has pulled all of its AdWords from Google. An informative BBC article blames increasing direct competition between the two Internet giants and reports that EBay used to spend $25 million annually on AdWords campaigns. This practice garnered the ire of some other users of AdWords users (like this one) for their incredibly vague keyword targeting. Google has canceled the most provocative action it had planned: a conference to compete with EBay's annual meetup.
It looks like EBay is preparing its own targeted ad technology and this may just be a convenient time for EBay to make excuses for cutting ties with Google.