Vikram Pandit, COO John Havens out; Michael Corbat to take over
                                
                                
                                    (Newser) -
                                    Citigroup CEO Vikram Pandit is leaving his post effective immediately, to be replaced by the bank's Europe, Middle East, and Africa head, Michael Corbat,  Reuters  reports. Chief operating officer John Havens is also stepping down, notes the  AP . "Now is the right time for someone else to take...