Search engines love responsive websites nowadays and implementing a website design with CSS3 media queries for responsiveness is the way forward as it avoids having a separate set of pages to serve a mobile site from the desktop version. Mobile visitors are on the increase and could overtake Desktop users this year.
Advantages to a responsive website
Mobile sites are designed to be less heavy on load time and therefore giving faster load times, making your users happy. One of Googles ranking factors is based on the speed of a website. People browsing your site on a mobile device expect faster loading times and need faster load times for being out and about browsing the web.
Here's a post on speed ranking factors from Google: http://googlewebmastercentral.blogspot.co.uk/2010/04/using-site-speed-in-web-search-ranking.html?m=1
In google analytics if you go to Behaviour > Site Speed > Speed Suggestions, analytics shows the amount of page speed suggestions to improve the speed of the pages on the site and totals a page speed score out of a 100. A high score shows there’s less room for improvement.
Next to the page speed suggestions, clicking the number opens an analysing tool and provides you with suggestions for desktop and mobile optimisation.
Alternatively go to https://developers.google.com/speed/pagespeed/insights/ for specific speed analysis of your website.
People using a mobile website should have a different browsing experience than a desktop as the mobile site should be easily navigational and generally stripped back to make everything easy on a mobile device.
Implementing responsive websites give a better user experience to users and therefore should improve your mobile traffic which you can monitor in Google Analytics and therefore should reduce the bounce rate of people browsing your website on a mobile website. You can grab specific information from Google Analytics to compare by going to Audience > Mobile > Overview and you can compare visitors bounce rate and average duration of visit to see what’s working best for your website.
Gives you a split of desktop to mobile and tablet
Looking further on the above data, I can see the bounce rate is less on a mobile and tablet device, however if the website was not mobile compliant, the bounce rate and average duration of a visitor would likely be worse than the desktop, because of the usability of the site, which gives weight to the importance of responsive websites and the importance this could have on the visitor converting.
Google has three recommendations for a smartphone optimised website, but the recommended configuration is that a mobile responsive website is built using the same set of URL’s that serve all devices and use CSS3 to render the site to the device in question.4th of June 2014 By Simon