Adsense like everything else we do online requires traffic to see real profits. The only possible exception to that would be quantity. After all 20 sites getting 10,000 visits per month might do as well as one site with the same amount of visits. That's assuming you can get good conversions out of those 20 sites.

Once you have that traffic it all boils down to testing to see what works best for your site. It's not just sticking those ads on your pages anywhere for those of you just getting started. You have to figure out where those ads get the best click through results...it might be at the top, middle, side, or bottom. You need to try different color combination's for the background, text, titles, etc. Testing is the only way to find out so try different options and record those results to find what works best for your site.

I wonder why everyone is so crazy about Adsense. On average, if you throw a lot of traffic to it, you could make roughly $1500. But some sites make only $340 a month. So you'd need a lot of Adsense sites to make a lot of money.