TheAnand

I am a big fan of testing ad units, primarily because it lets me find the best placements for a website. I think everyone looking forward to put in adunits to make money online in their sites should do it once the sites reaches 500+ visitors a day.

You should have seen this Google adsense heatmap by Google, which according to them should give you the right clicks on your site. But not every site has the same placements and the same audience, so testing and tweaking are the only ways you can increase your adsense revenue.