1. I have noticed using the leaderboard ad and then having four images directly above the ad will then catch the visitor’s eye and gives you more chance of your visitors clicking the ad.
2. People assume that using up the maximim amount of ads on one page will bring them more profit, i believe this to be not true. The more ads you have will one annoy your visitor and two spread the amount you could get from a click.
Spread the amount?
Let me explain say you have one ad at the top of the page with four lnks in that ad, you will have the top four paid ads in that google ad. Now say you put two more ad units on your site you will have 8 more links lowering in price meaning you could lose more profit assuming the click themn ads.
My advice to you is put the maximum amount of ads you can on your blog/site figure out which ads are getting clicked the most using the adsense channels and place just the one ad in the place which is getting clicked the most for maximum profit.
