Text ads seem to get a lot more hits. Place them directly at the top of a article but under the <h1> title. Make sure the URL tittle relates to the same content. Also try to get a few deep links with related anchor text to any internal pages.
For me, I prefer using text ads because of better CTR and higher CPC. It depends also on one niche to another.
The Google image ads seem to be of very low design quality too. I prefer Google text ads because I have CJ for image ads.
yep, you told me what i wanted to hear. I hate the image ads. they are VERY intrusive, but i wasnt sure how they earned, since we don't get any way to measure them separately. THanks!
Depend on niche and placement . i have one site on money making where image ads works fine because newbies their is free idea of making idea and than click click and click .
With text ads, a few different things might be displayed that catches the viewers eye. The image ad is usually instrusive and its only advertising one thing.
Yes you can track an individual ad, of course you can, create an image ad on your adsense setup tab, and start tracking it as an individual, try for one week than place an contextual ad, compare the two and see which one performs best. But I am telling you image ads don`t and never performed better than the contextual ads for one big reason, most are irrelevant to the content.
It depends of site. On some sites I have forced image ads only and it's looks and works better than standard text ads. But in most I use text wich works better inside text blocks.