Recently a Guest Post by Taylor Thompson of Video Blogging Tips wrote about the Adsense Default or so called Popular Blue Color Links Usage. As you guys probably already know, the best AdSense link colors are usually blue. The pros and Joel Comm himself will even tell you that a standard blue is the best blue for AdSense. However, this is no longer true. I have been testing AdSense colors for a few months now and have actually found that the standard blue #0000ff gets a relatively low CTR. This is probably due to either the * Color itself being outdated. * Color simply being too bright. More On The Article: http://www.smartbloggerz.com/2008/12/adsense-link-colors-standard-blue.html
I have to agree since i did some experience on using different colour, blue is the best but it only happen when your background colour is white. For the black colour backgrund, red is better than blue