Google is soon coming up with a new feature known as "Ad Review Center", which is particularly designed for giving more control to the web publishers who monetize their web sites with Adsense. The feature might be out in upcoming few months. It will permit web publisher review ads placement-targeted to the website, which would make sure those ads are applicable to your site's users. When you pick up the option for Ad review center, at first you would see all placement-targeted ads currently targeted to your site and after few days you would be able review placement-targeted ads that have previously run on your site. On the other hand, you have an option of blocking the ad from appearing again if the ads are not applicable to your users.