The Google AdSense blog posted about a newly developed tool called Ad Review Center, which provides more transparency and control over the ads appearing on pages. Google will be rolling out this new tool to publishers over the next few months to let you review ads placement-targeted to your site and ensure those ads are relevant to your site's users.
From AdSense blog post:
Google, AdSense, New Features, AdSense Features
When you first opt into the Ad Review Center, you'll be able to see all placement-targeted ads currently targeted to your site, and a couple of days later you'll be able to review placement-targeted ads that have previously run on your site. If you think an ad is not relevant for your users, you can prevent it from appearing again by blocking it in the Ad Review Center. We recommend you carefully consider the revenue impact of blocking an ad, since blocked ads won't compete in the auction on your site, and advertisers whose ads you block may choose not to target your site again in the future.
In addition to letting publishers weigh in on the relevance of placement-targeted ads, the Ad Review Center will also help advertisers improve their placement-targeted ad campaigns. When you block an ad, you'll be prompted to select a reason. We'll share this constructive feedback with advertisers so they can use it to improve the quality and relevance of future ad campaigns.
As we've done with past features, we're gradually launching the Ad Review Center to all publishers over the next few months. When it has been enabled for your account, you'll see a green notification box at the top of your 'Competitive Ad Filter' page, located under the 'AdSense Setup' tab. By default, the Ad Review Center will let you review all placement-targeted ads after they have run on your site. However, if you have a strong need to manually review ads before they appear on your site, you may do so by clicking on the 'update settings' link in the Ad Review Center. You'll then have 24 hours to review ads before they are automatically allowed to run on your site. Please note that you can also return to the Ad Review Center and allow a previously blocked ad, or block a previously allowed ad.
We strongly recommend you keep your review preference set to 'auto-allow' and review ads after they have run. Ads don't participate in the auction while they are awaiting review, and ads that you have blocked cannot compete in the auction either. The actual revenue impact will vary in each publisher's situation, but when using the Ad Review Center, please consider the revenue effects of blocking ads or switching from the auto-allow setting.
Learn more about the Ad Review Center.