I don't think flicking through TV channels is really in keeping with what the two minute silence is all about.
Personally, I'm not fussed about it. However, I would expect those who do support it to SWITCH THE TV OFF, stop what they're doing, and use the two minutes for thought, contemplation and remembrance.
It seems a bit silly and pointless to go flicking through TV channels to see if others are doing what you're not.