Why does anyone think Apple would need to sell an actual screen to change the way you interact with your TV? I don't see it myself. But maybe it's all based on rumors I've been ignoring.
Because the rumor is that Apple is making an actual TV. Frankly, all that's been talked about (Better content distribution, better remote control, Siri) can be achieved without Apple having to ship an actual TV set. So I don't see how the TV set rumors jibes with all of this or how all these other rumors support the idea of an Apple TV set.
The 99$ Apple TV box could do Siri, could do better content distribution, could do a better remote control, it could do CEC to control all your devices over HDMI, etc...
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Here's a possibility.
The thought just occured to me that content that travels via HDMI uses HDCP to deliver said content.
Now here's how Apple could make one remote for all those HDCP devices.
From Wikipedia :
"The system is meant to stop HDCP-encrypted content from being played on devices that do not support HDCP or which have been modified to copy HDCP content. Before sending data, a transmitting device checks that the receiver is authorized to receive it. If so, the transmitter encrypts the data to prevent eavesdropping as it flows to the receiver."
Now if HDCP requires a device to identify itself before sending the throughput couldn't the built-in Apple TV software automatically identify that device using the encrypted data sent via HDCP and tell the remote what the device is and add it to the plist file thus being able to automatically control said device ?
What you're talking about is part of HDMI, not HDCP, and is called CEC. It already exists. HDCP just valides that there's an encrypted channel between the devices. CEC over HDMI permits controlling a device remotely from another device.