I split off my slower second level pages(12) from Adsense to YPN and kept my indexes with 3 ad units and a link unit with Google.Less per click & 70% of the take but more targeting and pretty steady results for 4 months)
First week 4X the value of the Adsense returns on the B pages. Second week 2X, Third Week (just started) 3X.
When I went from 4X to 2X, I was sitting here going "say what". Everything was set the same as before but the click prices went down and I had Harley ads all over the place. Didn't really mind them but there was a lot of them which dropped my clicks down too.