I don't see TV as inherently bad - in fact, some of the kids programming on Treehouse in Canada is quite good!

I've sometimes regretted not watching TV for this reason. When I was in seventh grade, my friend called me 'culturally deprived'. A lot of kids watched the same TV shows and talked about them, and I didn't get the references. Whereas up until high school, hardly anyone had read the same books that I had. In a way, I was excluded from pop culture. And my general knowledge in areas that don't specifically interest me, like politics, is probably much lower as a result of not having been plunked in front of educational shows.

Still, I think that not having the habit of watching TV to relax outweighs those downsides. I'm able to get a lot more done in the time I don't spend watching TV.