Innovative and paradigm-breaking as CoE can be, I think even now we're still a bit too undeveloped in terms of technology to make the game fully voice-compatible. What I mean by that is inclusive of reactive NPC voicing (AI actually responding to player voice prompts), and having a functional proximity detection system that can handle an absurd number of people talking in close proximity with the right mechanics in play to make it sound and behave realistically.
I think we're close; provided Google doesn't screw up and accidentally unleash an apocalypse-scenario-AI upon the world, we should start seeing reactive NPC voicing pretty soon. Microsoft and Google already have their toes in the water, and it's not going to take too many steps from here before interactive AI becomes a more tangible presence in the datascape. We won't see it in CoE, but I think we'll start to see it in the games that follow.