I have loved Google adsense and have been a adsense publisher for 18 months now but when I was accepted to participate in the Yahoo Publisher Network August first I thought I would switch over about 20% of my impressions and see how it stacked up.
I rotated my YPN code about 1/5 of the time and the CPC end result was a 35% increase in income.
I am very hesitant to move everything over to YPN but I am increasing more YPN exposure across my sites all the time
The major incentive to me to move my sites from Google to Yahoo is the level of customer service. They provide you with a toll free number when you sign up and you can call and get someone on the phone in a few minutes. I called several times and asked questions ranging from advice on colors to ad placement to “IS THIS OK ?” you name it I asked it. I received instant answers and great feedback.
Negatives: So far I have not experienced any negatives. Yahoo really stole all the positives from Google and then added there own. I am sure I will have some negatives eventually but for now I do not have anything to offer here.