Jim Stengel, a successful and outspoken chief marketer of Procter & Gamble Co., has announced his resignation. In this interview, Stengel discusses new media, his legacy and his successor Marc Pritchard. Stengel says his work at the company over the past seven years has been about innovation, creativity and return on investment. "I think the magic is discipline and creativity. If you're off balance in either direction, you get off track," he said.