Google's debut of the Ad Traffic Quality Resource Center closely follows the arrival of a similar service from Yahoo. Click fraud persists in plaguing advertisers and the search advertising companies that sell ad space. High-profile lawsuits have happened as a result of businesspeople contending not enough is being done to keep their budgets from being tapped with illicit clicks. With trust occupying an important part of any online advertising product, Google and its competitors have to work hard to stay ahead of the various grifters, thieves, and assorted criminals who would loot their ad clients. They haven't always been very communicative about their work, claiming that the bad guys would profit from information about anti-click fraud efforts.
How about google itself http://www.google.com/adwords/adtrafficquality/index.html We'll see if something like that helps, I'm sceptical about it...
This will be interesting...as a PPC advertiser it sucks when you get really low quality traffic..especailly from content sites...it ends up costing you a small fortune dealing with the click fraud etc. But froma webmasters Point of view...i just hope that those of us with adsense accounts dont all get screwed when it comes to new TOS etc. With Google the devil is always in the detail etc.