Around May 8th, publishers believe Google introduced a bug preventing some new ads from being displayed in the review center. The first post about this wrote:
Has anyone else seen a lack of new ads in the Ad Review Center the past few days? I have it set to runs ads immediately and typically look at the Review Center once a day using the "new ads in the last..." dropdown to select 1 or 3 days. For the past few days, the 1-day and 3-day views are empty, while the 7-day view hasn't updated in a few days. Over the past couple months (since the new Ad Review Center was implemented), I would typically have dozens of new ads in the "last 1 day" view.
A publisher dug a bit deeper and believes this is indeed a bug. He wrote:
As a test, I changed my account from "Run ads immediately" to "Hold ads for 24 hours." The new Upcoming Ads tab appeared as it should, initially empty. I checked back in a few hours and it was populated with dozens of new ads. I switched back to "Run ads immediately" and the Shown Ads tab is again empty when I select 1/3/7 day views. Definitely looks like a bug that was introduced May 7 or 8.
Have you noticed this issue?
Forum discussion at WebmasterWorld.