by Charles Costa at SitePoint / Design & UX
Traditional site analysis tools always provide you with valuable insights into how popular your content is and the length of time users spend on your site. However even the best analysis tools are limited in the information they report.
Fortunately you can use heatmap and mouse tracking tools to gain insights into the minds of your users without the expense of setting up formal focus groups. Aside from being cost effective, heatmap tools have an advantage over focus groups because the user is naturally interacting with your product, often unaware that they are being watched.
read more at
http://www.sitepoint.com/using-heatmaps-improve-usability-conversions/