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Oh well. I wish people would focus on the long term and build sites that will survive the ebb and flow a single ad network. But then again, if there is money to be made . . .
Site may not have:
Pop-ups that interfere with site navigation, obscure AdWords ads, change user preferences or prompt a user to change his/her preferences (such as a userís home page), or are for downloads
Slick trick, I suppose, but will get the publisher one of those dreaded emails ;)