Before launch Nintendo showed off one of the more interesting non-game applications for the Wii U. ‘TVii’ will integrate your various TV and movie watching services, turning the gamepad into a pretty robust multimedia remote. You’ll be able to access video on services like Amazon Instant Video and Netflix as well as your DVR and cable/satellite. These services will obviously differ depending where you are in the world.
Unfortunately the service is not currently available and Nintendo have broadly set the release window at “December.” Some of the services do currently have apps however, Netflix for example, but they are obviously not yet integrated with ‘TVii.’
Source: Joystiq