I've put a 5 link text ad unit across the top of my pages (728 x 15) on a couple of sites to replace the larger text banner (728 x 60). How do these ads do on your sites? I noticed that the image ads (728 x 60) didn't perform as well as solely text ads - I reckoned it was something to do with the way they interfered with the look of the site - they just don't blend. My thinking is that people don't want to spend time on a website which looks like it is designed to serve ads. Do you agree with my thinking?