I would really like to see "JRiver On Android" running on my Sony Android TV, with a Theatre View style interface, and running as a Client of my MC HTPC Server.
I could then move my HTPC out of the loungeroom and out of sight, and just use the TV as I am currently using the HTPC. Of course, it would have to be capable of 4K UHD video, 3D, and the audio would have to be sorted, possibly using the Audio Out via HDMI on the TV, or maybe directly from the Server to my Receiver. Definitely some things to be sorted out there.
But being able to use a TV as a standalone Client, with Theatre View, and no other devices required, would be great. Particularly where the TV Audio capabilities were all that was required, rather than a full 5.1 surround sound system. Not that I have a bunch of TVs around the house, but some people do, and it would give me the option!