Costco, Citibank, Visa, and all of the companies’ customers had plenty of notice that the warehouse club’s store-branded credit card would be switching from American Express to a Citi Visa card. The transition didn’t go very smoothly for some members, but everyone assumed that the transition-related problems would be over by now. Nope. Some customers received cancellation notices at the end of last week, and are now very confused. [More]