Any one knows - how some publishers are allowed to trigger ads in bold and news H/L style. This will definitely get high CTR if blended with the site bg. -Which ad format get highest CTR?
Those publishers are premium. They get more than a million impressions a month so Google likes to give them more options. Currently, the large rectangle and the rectangle are the best performing ones.
It's against TOS to change the ad code with css. I have bold ads on my site sometimes too. But it's done by Google and you can't influence it unless you're a premium publisher.
Yea I know it's against TOS that's why I don't use it. I just tried it (OFFLINE) to see if it could be done.
It's all about blending your ads. The large rectangles will definitely get you most attention. Check out this post about the best AdSense colors.