"Which new model will work? No one knows at this point, but there will be billions of dollars for whoever figures it out."
Here is the point; don't limit yourself to Google Adsense or any other CPM or CPC; try to find sponsors interested on your site they'll pay much more better.
Thanks - I would like to hear form you, and from anyone else, who has been able to successfully break away from Google, Amazon etc to go on their own, esp early stage companies. Once you are known, and (may be) a popular site, then sponsors will flock to you.