There are no banners only pop-up ads. There are two different providers, one generating around 1/3 the other the rest. I get probably one inquiry a week to test new ad system, which I mostly do. This way I went up from 6-7k a month to beyond 30k.
I am extremely strict with what I count as a hit (I have a whole GEOip & browser combination) so if two people come from the same country with the same browser, it's only one hit, ever.