The_Contractor - 8:58 pm on Feb 5, 2005 (gmt 0) I for one see only positive changes in earnings and CPM.
Not that this contributes much, but you will normally have more people chiming in when things are bad, then if they are doing better.
I see nothing that would lead me to believe Google has changed anything as far as percentage etc. I believe those who see derogatory changes are seeing the affiliate policy of AdWords or other factors. Type of site and visitors are also going to have the largest impact. If you have a large percentage of traffic being repeat visitors on a daily basis your earnings and CTR etc. are bound to drop as time goes on.
I for one see only positive changes in earnings and CPM.