Philadelphia Inquirer: Al Gore made ’em laugh yesterday when he brought his climate-change road show to Philadelphia. Criticized by some observers for being too serious, too eggheaded, during his 2000 campaign for the presidency, Gore introduced himself during his Foreign Affairs Council keynote address with “I’m Al Gore. I used to be the next president of the United States.” When the audience cracked up, he deadpanned, “I don’t think that’s particularly funny.” He then pronounced himself “a …