Something very surprising ... could be a coincidence ... Long back when I started testing YPN (yahoo ads) on some of my pages, (I added YPN ads on a forum which was paying very very less per day ... less than a dollar) ... next day I found that my overall adsense income drastically dropped. Dropped for most adsense pages for my account. Found that traffic to my other adsense pages came down from google searches. Coincidence. Strangely 2 days back I turned on YPN ads again on a new section of my site.. and today I find that my overall traffic and subsequently adsense earnings have come down by around 30% !! Concidence. I believe in Google's Do No Evil policy... but these two coincidences for a minute made me wonder if somehow the big G has code to punish sites which use YPN ? I know its not true. Just wanted to share my observation.
Was your traffic and CTR constantly the same without YPN as with YPN? Did your CPM drop when using YPN?
Mine didn't. I used YPN ads as alternate ads on pages I had single adblocks on. That worked ok, enough to prove YPN could be worth something. I'm used to Adsense and YPN still has a few growing pains, but I can't say that I ever though it affected my adsense revenue.