I just noticed this new feature in adsense. Has this been open to people outside the US for long? Looks like ill not have to weed out the MFA's in the future! "Google Referrals allow you to choose specific products or groups of products to advertise on your site, allowing you to match ads to your content. Choose up to 15 products or specific ads to rotate in the referral unit. You can also choose categories and keywords to ensure that you get newer ads as they become available."
I can only find a link from the random "Tip" box in adsense. I refreshed until it appeared again. It reads: NEW Congratulations, your account has been upgraded to include the all new Referrals 2.0 - click here to get started The URL is here: https://www.google.com/adsense/referrals-settings