Key TakeawaysChipotle chief executive Brian Niccol will take over as CEO and chairman of Starbucks next month.The burrito giant's longtime CFO is also set to retire, though he will now stay on indefinitely in another role to aid the transition.Chipotle's leadership team has presided over a resurgent brand and a rising stock that recently split 50-for-1. Shares of Chipotle Mexican Grill (CMG) fell Tuesday on the news that the burrito giant would be replacing a heaping helping of the leadership that has helpe ...