A Google Now sort of service for the TV

Google Now is a superbly powerful Android feature; showing the user useful information without being prompted is something I'd really like to see more of. In light of this, I was watching the TV program Horizon: Tomorrow's World last night and thought it'd be really great if my phone would serve up relevant information based on what I was watching.

Often whilst watching a program I'll Google something from the show, or maybe search twitter for the show/presenter/actor etc. For example last night I looked up graphene and one of the scientists. I thought it'd be great if my phone knew that I was watching this program and served me this kind of information unasked, in Google Now cards or some other service. Microsoft's Smartglass service does something like this but I don't think it goes far enough. Maybe Google can add this kind of functionality to their TV, so that it knows what I'm watching, what the program is about, and who's in it, and shove that kind of information to me.

Just an idea, what do you all think?