The ideal situation. A page targeted to an audience. The audience is there ( not always the case.) And all the ads have to do with something else.
I know I should be happy that google gave me the two hours but you have to assume this is repeated a million times a day.
I've seen this effect but on the other end. On one of my websites, ads (from adsense) about a certain product was 100% relevant and were showing 100% of the time, click throughs went right up, until I had to change something, cant remember what it was now, but I seemed to have reset something and the ads like those never came back.
Our esteemed moderator, ewhisper, just posted a killer blog post about the Content Network on his blog yesterday. I can't give urls out, but if you do a Google search for bgtheory, I'm sure you'll find it, and it may help.
I am pretty sure that both netmeg and eWhisper know more about AdWords than I do. So I endorse this advice wholeheartedly. :)
AWA