Twitter positions itself as an accompaniment to watching TV. There's a term for it - double-screening. You're watching one. The other's on your knee.
Double-screening works best with TV that requires low engagement. Eurovision, X Factor, a football match between two teams you don't support. Somebody in advertising told me that they can track the amount of conversational "noise" on programmes of that kind. It continues all the way through.
On the other hand programmes that require high levels of engagement, such as Homeland, are preceded and followed by lots of Twitter traffic. While the programme's on people are too busy watching. Makes sense.
I wish somebody would come up with a name for the shows of enthusiasm that Twitter increasingly tempts people into. I'm getting the feeling that people's desire to be seen to enthuse about some new things, particularly in music, is greater than the actual enthusiasm they feel.
Media can't hype people any longer but they're quite at liberty to hype themselves.