It depends. Getting rid of ALL tv could be a bad thing. But if you left the intelligent or at least somewhat educational programs then it would be a very good thing. History, Discovery, Food (free cooking lessons), and the News are obviously the "acceptable" ones. For kids and teens they could include one or two programs that contain cartoons and such (with some educational value). ABSOLUTELY NO MTV, and no Nickelodeon.
I used to waste all my time watching tv but now I spend my free time (limited due to a lot of after school activities) on the computer looking up answers to whatever curious questions I come up with (ie. Space, Alternate universes, Time travel, etc..). True I could go to a library but I tend only to read books that catch my attention, not research books. I feel I somwhat have Harry Potter to thank for getting me away from the tv, but I did read a lot of books before Harry Potter. I was just growing a tad lazy and forgot my love of books until the series came out.
Now the only time I watch tv is a little before I go to sleep to help me unwind. And on the weekends my tv is mostly used for video games. Also I hate to say it but I do watch reality tv shows like Big Brother, and Survivor (used to watch Amazing race, until they made family addition). What can I say, I like to scrutinize people, and see how they react in certain situations.