Jakob Nielsen and Kara Pernice, recently published, Eyetracking Web Usability. In this they explore they way in which we read web pages and how we react to different stimulus. What does this mean for ads? According this study, pretty pictures aren't going to get you too far, banner blindness is real. So a few findings are that still text based ads work, but we know that from the profits that Google report each year. Faces also attract peoples attention, though arguably a mass of faces appearing around a site, could be very off putting. 

That being said it's not all bad for the advertisers, creativity and innovative solutions that are keenly integrated into content areas will work, especially the more they are 'designed' in. The balance will have to remain between publishers keeping integrity with its audience, displaying relevant which flow as a natural part of content and design.