From the Yahoo Search Marketing Blog:
Yahoo! Search Marketing is rolling out a new feature that we think will help enhance the quality, potentially reduce the cost and increase the value of traffic to you, our advertisers. It’s called quality-based pricing, and it measures the quality of traffic coming from our distribution partners—that is, the web publishers large and small that display your ads.
Previously, you were charged the same for traffic from all web sites within our distribution network. Now, with quality-based pricing, you may be charged less for certain clicks than you otherwise would pay, depending on the overall quality of the traffic provided by our distribution partners. As a result, your click charges can decrease.
“Quality” is calculated based on conversion rates and other measurements of the ability of our partners’ sites to deliver more interested, valuable customers to you.
Welcome to the world of managing publisher expectations and naunce, Yahoo. This will be interesting…