I started using Chitika eMiniMalls a few days ago on Free Horoscope Daily, as well as on the tools pages of this site. So far so good, it seems like a very promising ad service. The ads can be contextual like Google Adsense, but I suspect you can get them to perform better by specifying keywords to bring up the product you want.

Very recently, Chitika added a JavaScript variable to allow for Channels, ch_sid. Instead of having a Channel management area on the website, where you set up channels and get a numeric ID to use for the channel, they allow you to specify any string at all. This makes testing out different ad styles and keywords very easy.

To test out keywords, that is, to see which keywords bring up products people are actually buying, we can create the Channel name dynamically using Javascript:

ch_queries = new Array("ipod", "camera", "dvd player", "etc.");
ch_query = ch_queries[Math.floor((Math.random()*ch_queries.length))];
ch_sid = 'Channel Prefix ' + ch_query;

This will give you channel names like "Channel Prefix camera" or "Channel Prefix ipod", etc. Of course, you can change Channel Prefix to include more information on the type of ad or location of the ad.

You could also experiment with different ad colors or sizes in a similar way, and build up the ch_sid variable to include all the variables. For example:

ch_colors = new Array("red", "blue", "green");
ch_color = ch_colors[Math.floor((Math.random()*ch_queries.length))];
ch_sid = 'My Website ' + ch_color + ' ' + ch_query;

You get the picture. Of course you can do all this with Adsense too, you would just have to set up a channel manually for every color / size / location combination, then dynamically associate the combination with it's channel ID. Quite a bit more painful though.

Chitika also allows you to test out searches on their website. They actually recommend you go to Amazon or Shopping.com and find best selling products, then try to create keywords that bring up that specific product. And with this Javascript, you can determine what the best selling products really are for your visitors.

Have fun optimizing your ads!