I can do some of this already with my Sony Xperia Arc connected by HDMI cable to a Sony Bravia set. The touchscreen on the phone shows up on the set. I can use the TV remote control to change things on the phone just by beaming an up or down command to the TV screen. When I use voice search I have to use the gesture of the phone to activate the search and that's a bit cumbersome when the HDMI is connected. But it's relatively straightforward to remove the gesture and to activate the search by talking. However, in a chatty sitting room, that could create channel surfing when people started talking. I'm playing with the system now, discovering Google's Mobile app can find my local files. That means I can ask the phone for a photo gallery and the TV set cues the photos for slideshow viewing.
I'm putting this blog post up for Christmas 2016 reading in the hope that my voice-activated search will also understand the electronic programme guide on the television set.