New Yahoo (YHOO) CEO Marissa Mayer late Monday gave her first public update, saying she wants to push the company toward redesigns for popular products like e-mail, and investors on Tuesday responded by pushing the stock up. Shares midday were trading near 16.65, up 5.6%. Mayer's discussion on Monday came as part of the company's Q3 report, and was the first time Mayer's been on a conference call with analysts since she was hired away from Google