Starbucks's chairman Howard Schultz speaks during an interview with Reuters in Mexico City September 7, 2007. Starbucks Corp on Monday said its chief executive, Jim Donald, is leaving the company, effective immediately. Schultz, the coffee shop chain's founder and chairman, will take on the CEO role. REUTERS/Henry Romero By Nichola Groom Reuters January 7, 2008 LOS ANGELES (Reuters) - Starbucks Corp announced on Monday the immediate return of founder Howard Schultz as chief executive and the slowing of an aggressive U.S. expansion in a shake-up that sent its battered shares up nearly 7 percent. The move marks the return to daily management of the well-liked chairman, who is seen as the conscience of the company after he warned a year ago that Starbucks was losing its way. Investors have nearly halved the value of the world's biggest coffee chain to $13 billion in the last year in the midst of weak U.S. sales growth and encroachment by competitors. "The most serious ...