In a sign of the (social media) times, Mexican President Felipe Calderon used Twitter this morning to warn his people that Hurricane Karl could hit Mexico as a Category 4. By mid-afternoon, his tweet had been quoted or mentioned in newspapers and radio and television stories around the world. "An alert for Hurricane Karl in the nation's central states," President Calderon's tweet said in Spanish. "[It] could convert to a Category 4. It will enter through Veracruz … [Read more...]