In many cases, mobile advertising still feels too early and players in the value chain don’t seem to be in sync. Ebay is deciding to remove mobile ads for now:
This year, eBay displayed ads inside of its iPhone app as an experiment, but found that they were distracting and cluttered up the smaller screens. The ads also didn’t deliver meaningful revenue. via eBay to Stop Advertising Inside Mobile Apps: “It’s Not Worth It.” – Tricia Duryee – Commerce – AllThingsD.
I’m not sure I would pull back my foot in the mobile ad door though. In this world, the biggest delta is relationship driven and it helps to have a presence in that world or you might find yourself several steps behind the competition.