Aiming to stake his claim to the tech-savvy young voters who helped elect President Obama, San Francisco Mayor Gavin Newsom, 41, today took to the new media to formally announce he's running for governor - by directly addressing hundreds of thousands of supporters simultaneously via YouTube, Facebook and Twitter. "We can't afford to keep returning to the same old tired ideas and expect the same result," the Democrat told supporters in his three-minute YouTube announcement, part of the unprecedented "virtual fly-around" campaign announcement done entirely in the new media. The gubernatorial candidate's announcement video, which premiered on his Web page,...