<p> Carolina Panthers coach Ron Rivera has joined social media.</p> <p> Rivera started a Twitter account called @RiverboatRonHC, based on his "Riverboat Ron" nickname.</p> <p> Rivera has sent out a couple of Tweets already.</p> <p> That included a link to an ESPN story on Panthers quarterback Cam Newton spending time with Make-A-Wish child George Gring.</p> <p> Rivera is already over 2,500 followers</p> <p> Follow me on Twitter: <a href="http://www.twitter.com/RavensInsider">@RavensInsider</a></p> <p> Aaron Wilson covers the Ravens for The Baltimore Sun</p>