but the _commercials_
When paying/working/whatever on a computer you're generally focussed and have a general control over what you see/do.
On TV, especially kids TV, any program you're watching is frequently interrupted by images and messages about junk food, snacks, sodas, sugar-laden juice drinks, etc.
I contend that it is this (subliminal" maybe) messaging that's leading to obesity as much, if nor more so, than just the sedentary nature of watching TV.
Change the computer so that every for 2 out of every 8 minutes of usage your computer screen is replaced with images of BigMacs, Whoppers, Coke, Skittles, etc., etc. and I BET that all those non-fat computer kids will get fat pretty quickly.
Damn, did I just give the junk food industry a new target to aim for?