PayForIt - New UK Mobile Phone Payment System

A new payment system will be started soon in the UK which will turn mobile phones in to digital wallets. Recently the 5 mobile networks in the UK reached an agreement on how it will work. The system is called PayForIt. The PayForIt system will allow you to spend up to 10 pounds on items such as train tickets, parking and other similar services. Money spent with your mobile phone will be added on to your bill. When money is spent a digital receipt is sent (maybe via MMS?) to your phone so you can keep track of your purchases. The only worry I have is that your phone could become like a credit card in that you could spend lots and then get a bill at the end of the month. Hopefully for those with spending habits, a cap can be put on how much can be spent each month. Hopefully interest will not be charged either.