I think you're confused. We are talking about the controller connection, not the console connection. They still have the optical out on the console for high-quality audio. This is the controller adapter they are talking about, not the console audio out. The controller audio only consists of voice chat and mic on the 360.. but will include full stereo game audio on the new controllers.
Not sure they are locking out the headsets. They have changed the way the controller communicates with it's peripherals (headset, mic, keyboard, touchpad..whatever). Could they have made it backward compatible? Sure, but they decided to design the console as a new console without making concessions to older hardware.
I would prefer a console that is envisaged, designed and built to be the best they can, rather than include compromises for older hardware. I want it to be as good as it can be, as it's got to last 5 years or more.
Sure, I'd be pissed off if I'd invested in a great headset I couldn't use on the XB1, but they're making an adapter.
The controller is no longer just mono, so you can get full game sound through your controller.. meaning you don't need your 4 meter lead back to the console. This also opens up the potential for multi-player split-screen players each getting their own game audio feed (rather than just chat).
They've reduced latency and increased bandwidth by switching to WiFi direct (over some sort of proprietary RF system they were using on the 360).
All-in-all good design and good product decisions.
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