Here is the quote by Phil Harrison from Microsoft:
“There are many devices in your life that require the Internet to function. Xbox One is no different in that it requires, at some point in the beginning and at various times through its on state, to connect to our cloud and to our Internet. That is to deliver Xbox Live functionality, that is to deliver download content to you, that is to deliver some of the innovations around TV and entertainment that we showed today. But it doesn’t require it to be online all the time.”
“For single-player games that don’t require connectivity to Xbox Live, you should be able to play those without interruption should your Internet connection go down. Blu-ray movies and other downloaded entertainment should be accessible when your Internet connection may be interrupted. But the device is fundamentally designed to be expanded and extended by the Internet as many devices are today.”
