With the smart pricing I believe Adsense and YPN are hurting themselves more than the pubsishers. When the publishers see a signivicant drop in revenue, they'll looking for better ways to utilizing the most of their ad space and truffic. With less ads on the publishers sites there will be less revenue for them. Smart pricing is a double edged sword IMO. They have to be really careful with it.
but maybe for long run it's better to sustain their business model if advertisers ROI keep decreasing, eventually nobody will advertise anymore that's what i think