Did you know that xbox one will automatically download additional game content for your games???
(unless you are clever enough to find the carefully hidden option on the dashboard that allows you to switch automatic downloads off)
So, your console will be scanning the net all the time for game updates and add ons, and will donwload them automatically for you. And the servers will then charge you for them. You will be getting uncomfortably huge phone bills like all the time, untill you finally realise that the culprit for those bills is your new xbox one!