The future of money is, that most probably paper money will be replaced with plastic money. But paper money will be in use many years ahead. Many poor countries from Asia, etc. are using only paper money, they do not have Internet connections in shops - so, they can not use credit cards. 
Paper money can not be replace of plastik money like credit card becuase paper money is use all over the world and it is hard to replace it as you sais many country poor they can not provide to get a credit card so nothing can replace our paper money.