* Ebay is worried about having no ad network when its competitors do. By farming out the U.S. business to Yahoo (YHOO) and the non-U.S. business to Google it trying hard to protect itself, which may work in the short term, but is a dubious longer-run strategy.
* Short-term, I'm surprised that this will not affect eBay's 2006 or 2007 results. The upshot seems to be that eBay will only start testing the arrangement in early 2007, so that puts 2006 materiality out of reach, leaving 2007 still possible. So why no impact there? eBay is clearly planning to go slow, perhaps keeping its options open with respect to ad networks.
* If needed, this is a lovely example of how every software service is also a media service. While it took eBay too long to get over itself, any high-traffic application that does not also run ads is passing up material revenues, and its shareholders should take it to task.
GOOG-EBAY 1-yr comparison chart: