According to Jakob Nielsen nobody looks at picture advertising online:
â€œWe call this banner blindness â€” people wonâ€™t see ads at all,â€ said Nielsen. â€œAds might as well not exist as far as users are concerned, except for search ads.â€
Okay… so you read the link. Remember any ads??
Fortunately, search driven ads (i.e. Google Adwords) work just fine:
â€œWe thought weâ€™d find [paid search] box blindness the way we did banner blindness, but thatâ€™s not the case. Users are interested in search ads and actually look at them.â€
In my own experience this is quite true. Both for me personally as I browse the web and also as a buyer of tens of thousands of dollars of online advertising. Search based advertising works well but must be watched carefully for efficiency. Image/banners ads, hardly work at all.