This is a great test to see how well you have built your web page, or hopefully how well someone has built your site for you. Take the Blink Test. Successful blog has a great article and link to how you should look at your page only after it loads or look away from the screen and note what the first thing your eye navigates to when you look back at your website on the screen.
Is what you see important and what you want your customers to focus on first? Or do you notice some kind of advertising first. You have to make sure that your customers see your message as soon as they see your page or your site may be forgotten forever.