Syrian leader Assad's planes pound vital prize of Aleppo

ALEPPO, Syria (Reuters) - President Bashar al-Assad's forces used artillery, planes and a helicopter gunship to pound rebel positions in Syria's biggest city, witnesses said, in a battle that could determine the outcome of the 17-month uprising. After U.N. Security Council paralysis on Syria forced peace envoy Kofi Annan to resign last week, and with his ceasefire plan a distant memory, rebels