Huge drops in CTR, the announcement of "Estimated" earnings wording, delays in stats. I wonder if Google opted us in CPA or just increased the percentage of CPA ads since late December.

Also the ability to import Analytics goals to Adwords as Conversion tracking made it easy to switch CPA pricing for advertisers. There are new types of goals in Analytics, "time on site" and "pages/visits". It is far more easy to setup conversion tracking and switch to it.

The delay of stats in Adsense is similar to the delay of Analytics stats. So maybe Adsense waits for action confirmations and reports as estimates...

Does this make sense?