I stopped watching TV regularly about eight months ago when I got my first "grown-up" full-time job. Before that, I was in school and working part-time, so if I spent a couple of hours on my butt in front of the TV, it didn't matter because I had plenty of free time. Upon reaching the cold, hard world of corporate America, however, I discovered that my free time was precious--I was working not because I enjoyed it, but to support myself, so I had to make the most of what free time I had to justify the sacrifice of nine+ hours a day. I cut myself off from TV and cable and haven't regretted it yet. Since then, I've done more (even if that 'more' is only going for a walk or going to the gym) and I've lost weight--about fifteen pounds, all due, in my opinion, to the fact that if I was watching TV, I was eating, as well. In additon, my insomnia has virtually disappeared. It used to be that it would take me at least an hour every night to fall asleep, if not two. Since I gave up television, that period of unwilling wakefulness has shrunk to maybe a half an hour a night--but if I watch TV right before going to bed, it will still be about two hours. Television was ruining the basic biology of my life (eating and sleeping being pretty key factors), and I didn't even realize it at the time.
Anyway, I found a disturbing statistic online today--apparently, the average American watches 28 hours of television a week. For those of you who aren't up on arithmetic (7x=28, x=?), that equates to about four hours of television every day.  Four hours? That means that the average American gets home, turns on the TV and watches it until they go to bed at night. Is it coincidence that the average American man also weighs about 27 pounds more than the average American man did thirty years ago?
The damages from TV are mental as well as physical, however: "when you're watching television the higher brain regions (like the midbrain and the neo-cortex) are shut down, and most activity shifts to the lower brain regions (like the limbic system). [...] The lower or reptile brain simply stands poised to react to the environment using deeply embedded 'fight or flight' response programs. "  Television effectively turns us all into zombies, and while most people are aware of it, no one is doing much about it. One of my co-workers come in every morning and asks, "Did you watch The Bachelor yesterday?" When I say, no, I don't watch TV, she replies, "Oh, neither do I. But last night was different." She knows it's bad for her, and she knows she shouldn't watch it, but she still does every night, justifying that 'today is different.'
I can't help but think that Plato's "Allegory of the Cave" is incredibly applicable to this situation. Americans are sitting on their asses staring at the wall, and when things pass in front of the light, they can't recognize them as what they are--in this case, addiction and the death of the imagination. If you haven't read the allegory, you should--you can find it in The Republic. Better yet, you should read Brave New World to see just what we're becoming. Come on, people. Would it kill you to read a book?
 "Media Statistics." http://www.nationmaster.com/graph/med_tel_vie-media-television-viewing
 Moore, Wes. "Television: Opiate of the Masses." http://www.familyresource.com/lifestyles/mental-environment/television-opiate-of-the-masses