Nowadays, the rapid growth of mobile web browsing is so significant so traffic analytic web site likes quantcast have been working for several months on a methodology change to their traffic reporting in Quantcast Measure incorporates both first- and third-party cookies. Quantcast mentioned that you will likely see an increase in traffic, particularly for the mobile web.
That is also true on google analytics. One of my sites report shows(Aug 20th 2013)
This data confirms in the article “Mobile web browsing leaps to 27.1% of travel website traffic” .
The most money making ads size is 300x 250 medium rectangular unit which is the highest industrial demand for advertisers that shows that mobile web browsing is so significant as well.
In fact, if your website in not ready for mobile, your site will be in the dark ages. Be ready for mobile supported web. You may test your site at MobileTest.me and see how does your site looks in mobile devices.
The previous statistic from google has confirmed the above result after 10 days. (Aug 31st 2013)