Again fron Cutts:

"Google found multiple bloggers that violated our quality guidelines and we took corresponding action. Those blogs are not trusted in Google’s algorithms any more.

We do take the subject of paid posts seriously and take action on them. In fact, we recently finished going through hundreds of “empty review” reports..."

We talk, we read rumors, we often assume and we experiment - this is the nature of the industry. But if there is a clear "don't do it" warning form Google, I wont.