When using contextual ads – such as Google Adsense – one of the problems you are facing, is the obvious way the ads are displayed. It is no secret people try to stay clear from advertisements, and if given a choice, most would rather click a random link instead of an obvious ad.
If you use text links from various affiliate programs instead of Adsense, you will have a much greater chance of having people clicking your links, instead of just glancing at them seeing nothing but the "Ads by Google" under the ads.
Using affiliate programs correctly will give you several ways of increasing your revenue, it’s not just the placement and style of the ad;
Banners or text links
Although nearly all contextual adverting allows you to choose between banners and various forms of text links, using the banner option leaves you with no way of ensuring the design and colors of the banner won’t mess up your site. With a static banner from an affiliate program, you know how it looks – No surprises here. Combining banners and text links are much easier when you are deciding exactly what to put on your pages, not a script.
With Adsense, you are relying on the advertisers to figure out catchy and well converting anchor texts for their ads. Much in the same way, you can’t do much about typos, grammar or bad language. Although there are filters of various types – i.e. adult language and content – advertisers who try hard enough have little or no problems getting by many of these filters.
Number of affiliate links
The predetermined ad blocks do not always fit your web design and the same applies to the number of links. Working with affiliate programs, it is up to you how many links you add to your pages, making both the design and readability of the ads far better than a ready made website template ever will.
One thing most contextual advertising have in common is the simplicity. It doesn’t matter if you are an advertiser or a publisher; the quick and easy ways of implementing the ads often makes it easier to choose Adsense than it is to use an affiliate program. On very large sites, contextual advertising serves a purpose as part of the advertising – especially on pages with limited traffic. But, on pages with large quantities of traffic, choosing one or a few well converting affiliate programs will be worth the effort.
Size of commission
The main upside of affiliate programs is the commission. The commission is generally higher than contextual ads, but the most important thing is; you know what you get paid. Adsense – and most other contextual advertising – relies on advertisers bidding for keywords, thus making it hard – not to say impossible - to predict the revenue. With affiliate programs, you are offered a predetermined commission per sale, lead or click, making it easier to calculate your earnings. On the other hand, people researching Adsense keywords and their estimated CPC can make you a fortune if doing it right. But, for the rest of us, affiliate programs will be the more lucrative choice. If you just have the time and patience.