Edwin - 11:51 pm on Jun 30, 2008 (gmt 0)
I saw this note inside my Adsense account "Note: Referrals is being retired during the last week of August 2008, so we recommend that you do not implement referral ad code on your site at this time." but I didn't see anyone talking about it here. They have a whole section inside their Help Center about the end of the Referrals program. Basically, it will end for both Google products and 3rd party products.