How long should one give for new placement (and ads color) to deduce whether the placement & colors are working for him or not ? What sort of traffic is best known for clicking on ads ?
truly depend on the niche - sometimes its just one view that makes a click and sometimes it may be 1000views without any click... and if you are asking that which placement works best - then test it for 24hrs and during that day which gives you the most views in the week... hope this helps...