Welcome to WebmasterWorld Guest from 188.8.131.52
If you believe that another site is abusing Google's quality guidelines, please report that site at [google.com...] Google prefers developing scalable and automated solutions to problems, so we attempt to minimize hand-to-hand spam fighting. The spam reports we receive are used to create scalable algorithms that recognize and block future spam attempts.
I know a guy that's a premium publisher. His site still shows "ads by google".
I did not mean that no premium publisher has the text "Ads by Google", but some don't.
As Jenstar says, this isn't something that publishers can normally manipulate (at least not within the limits of my technical knowledge!), so I assumed it would have to be something else; "premium publisher" was the only thing that came to mind.