I changed the look of the adsense for search to blend in more with the background and it's giving me less clicks on my news blog, only two today. Typically I would have 4 or 5 by now. I will change it back to the black background
I think it is annoying when the ads stand out too much, it the ads are blended in with the site color and placed in strategic areas then readers don't mind them as much and even click on them.
When I added Google Search it immediately added over $50 per month in clicks to one of my sites. Google search works well for sites where visitors are searching for specific information. I have other sites that it doesn't do that well.
Ive tried it for about a month now and find it gives good CTR although not many use it - but that may be down to the type of my traffic. It doesnt take up much room so i think its definitely worth having.