Beware of some 'conditions' which apply to the Cash Back Card issued by Citibank, most of which is not in the Nikon advertising at all. You cannot get cash back on the card at an ATM, you have to purchase something. The Card attracts a monthly 'Account Management Fee', currently £2 per month but variable, if no purchases have been made after 6 months. If the card expiry date is reached and no extension has been requested before that date, Citibank help themselves to the entire balance. I have never experienced a credit balance being subject to Management fees before (seriously, what management?) and where the balance can be so easily lost. I am in the process of communicating with Nikon to get my management fees refunded and secondly, amended and additional wording placed into the promotional material and website pages.
So by all means take advantage of the cash back offers, but spend the money at the earliest opportunity. I note that all the other cash back offers by competitors involve the payment by cheque!