Philadelphia Inquirer: Vice President Biden convened the White House’s Middle Class Task Force in Philadelphia yesterday for a daylong inaugural hearing on the promise of prosperity in thousands of “green” jobs expected to be created by the drives to make the nation energy-independent and reduce global warming. The event, in the Irvine Auditorium at the University of Pennsylvania, featured questions from six cabinet secretaries, testimony from eight experts, and a bevy of public officials, including Mayor …