[kreilly]

"We generate money by serving Google text advertisments [sic] on a network of hidden Websites."

They are not really ads that are viewable by consumers. Most likely bot traffic.

[smartician]

Possibly related:

http://www.behind-the-enemy-lines.com/2011/03/uncovering-adv...

[mcv]

I thought Google was pretty good at detecting that sort of thing.