Everything should be in balance. And a LOT depends on what they are watching.<br />
My kid isn't really interested in watching TV though. He mostly likes to just have it "on", and oddly enough, he doesn't seem to care what channel. We spend a bit of time listening to the news.
A time to play and a time to work, a time to cry and a time to laugh. a time to watch tv and a time to We actually didn't have tv when my kids were young and I'd go outside with them and teach them all sorts of things like making forts and tunnels and swings and treehouses and and and and. When we were inside they learned how to bake cookies and pull taffy and bake bread. When we did finally get tv, they were 10 and 11. They loved watching it and I loved the break. lol . But they'd end up getting bored and go outside to play. By this time they knew how to entertain themselves and it worked for all of us. Now they are grown, but we still like going on hikes together, climbing waterfalls and swiiming in the ocean. We still make bread together and recently added making cheese to our list.
we raised our kids w/o TV until the youngest was 14. Now, we have sat. TV, but rarely watch live TV, except for football/hockey. we record the few shows worth watching, and watch the odd movie.<br />
we made the decision not to raise our kids with TV, and now they are ALL very active, outdoorsy, adventure seeking fun loving outsiders, not fat, lazy tv junkies. glad we did it, would do it again.
Only after they are 4-5 years old pref later. No ads.