SEOMOZ, the premier SEO researchers did a study on where exactly Google #1 search result placed on a computer screen. Search engine companies have known for some time, viewers look at the first three results. (At the top of the page).
This past February 10, SEOMOZ searched with Google using 10,000 keywords in 20 categories. Vertical positions of results, given in pixels, was calculated. SEOMOZ chose the keywords with the greatest amount of pixels from the top.