I was reading this disturbing thread over at Search Engine Watch Forums named AdSense For Domains Garbage Traffic. The thread shows how one AdWords advertiser that spent "20K+ dollars worth of garbage traffic that came as a result of parked domains and similar types of sites." He even notes that a "couple of the sites are porn related." Now now... I remembered that Danny wrote about this in the past, the past being only two days ago, under a blog entry he named Google AdSense For Domains Program Overdue For Reform.
Danny describes the AdSense for Domains program and shows how often, it leads to poor results for the advertiser and the end user, but great for Google and the publisher. Danny asks for the minimum;
At the very least, Google should make AdSense For Domains a program that really is independent of AdSense For Search and allow people to opt-out. It certainly should be pondering the mixed message of telling AdSense For Content people that they can't put ads on parked domains on the one hand yet running a massive program that does exactly that on the other.
Forum discussion at Search Engine Watch Forums, where they are on the topic of advertisers opting out of parkdomain (Google AdSense for Domains) program.