Thel links need to stand out. The background of adsense ads is usually white, so blue stands out the most whilst still looking professional.
I have always blended colors to match the rest of the site for aesthetic reasons and have some great ctr where the ads exactly match what people are looking for and poor when the ads do not. I would think this would effect ctr more than the color of the links ie if the page is about parrot food and the displayed ads are about 'buying a parrot' then the ctr will be alot lower than if the ads were for 'cheap parrot food'
I Think You can use Same color as you use in your Theme/Template Link Its really working Tested By me . - Hope its useful for You -
It is right that the blue color links have better clarity and appealing comparing other colors. So far I used yellow back ground and black color. I didn't have any good clicks. Now I shall try with blue, I think.
i don't think that blue color matters but blending your ads with your sites font colors actually helps.
I personally believe to convert higher I try to blend link colors with those of my websites design as a lot of people are doing currently, doing tests on both "Blue" links vs. others, the blue links didnt really convert / get a higher CTR.