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Obviously, mobile is important and it is just as important to configure it properly so that GoogleBot and search engines understand what is mobile and what is not. Without that, your mobile site may not be recognized and ranked properly by Google and more importantly, your users may get a bad user experience.
Google shared a really nice and easy to understand graphic that shows the response you should see when you have separate URLs for your mobile site and when you run it through the Fetch and Render tool within Google Webmaster Tools.
If your mobile pages use different URLs than your desktop pages (such as m.example.com or example.com/m/), test both mobile and desktop URLs in Fetch as Google to make sure that redirects are correct. In this picture's example, mobile users accessing the desktop URL (path: /) are correctly redirected to the mobile URL (path: /?m=1).
If all looks good, then move on to ensure your mobile site passes the mobile testing tool.
Forum discussion at Google+.
