But for those who want the complete experience, those willing/needing to upgrade/replace what they have (yes, people do), then heck yeah Apple should offer a tablet-thin integrated everything-exceeds-user's-perceptions device. Give me an iPad in 42" and 55" versions (same specs, just bigger).
Having worked in Kodak's digital cinema department, I'm cursed with spotting all the shortcuts everyone's big, thin metal & plastic boxes with large screens take to keep those prices down. EL backlighting? I see the inconsistent intensity. 60Hz? 120Hz? judder-inducing compensation for 24fps content. LCD? image persistence. You get the idea. Most of it comes from making do with what's already in the credit-driven supply chain. Would that someone like Apple have the wherewithal to pay big bucks up front to get the
right display built, something whose specs are good enough (a la "retina") that specs just don't matter. Build in the

TV3, include whatever cameras/sensors needed to enhance the experience (can't just slap those on someone else's big, thin metal & plastic box with a large screen), and then we have a complete experience nobody else can match (yet).
Upshot: the more I think about it, the more the built-in camera/sensors is a HUGE deal - stuff that changes the total experience that much can't be retrofitted in the Apple way. Out of the box, onto the wall, "Good morning, Darryl."