There are several threads at DigitalPoint Forums around the topic of seeing the "new" AdSense Ad Review Center. The thing is, the Ad Review Center is not new, at least not to me and many others. I assume that maybe it was a US roll-out until now and now Google has been rolling out this feature more globally.
Google began testing this feature back in December of 2007, we then received confirmation that this feature is real. So I demonstrated how you can block advertisers with the tool.
On August 4th, we reported that on an Ad Review Center bug, which was resolved a day or so ago. AdSenseAdvisor wrote at WebmasterWorld:
we understand that some publishers, who have set their placement-targeted ads to be automatically approved, have noticed that these ads are not appearing under the Allowed tab in the Ad Review Center.This issue has now been resolved, and you should be able to see your ads should appear under the Allowed tab as normal.
If you encounter this issue again, please let me know and I will escalate to our engineers.
Forum discussion at DigitalPoint Forums & WebmasterWorld.
