David Robertson at hooktraffic.com undertook a number of tests on both Google and Bing search interfaces on mobile and desktop devices through Feng-GUI.
Increasing your conversion rate is a truly important component of managing a website. As you are proactively tuning your website to increase sales or whatever you consider as a conversion - without increasing the number of visitors you receive. Often small changes to the layout or the color of a button, or changing the words on the button will increase your conversion rates. But you really need to do some precursor work and testing.
Read the full article at: http://www.hooktraffic.com/conversion-rates-why-bing-needs-to-pick-up-their-game/