Citibank's head of credit cards, Julian Potter, is to take over as head of the bank's Australian consumer business. Citigroup announced yesterday that Potter would succeed Roy Gori, who has been promoted to a regional role in Asia.Potter takes over 18 months after Citibank adopted a new business strategy, moving from its long held position as a mass-market brand to a focus on what it calls the "affluent and globally minded" segment.Potter has been involved in this change, overseeing the launch of high-end credit cards, the revival of the Diners Club card and the launch of a card-holder dining program.Challenges that Potter will have to deal with include Citibank's chronically weak customer satisfaction rating and its uneven performance in attracting deposits and selling mortgages.