When I traveled in to the office for work, I used to watch a bit of the morning news headlines, then when I got home, I'd watch the evening news (national and local). I agree that there was a lot of slanting on different networks and would try to find the station I thought at the time was the most neutral. But like others have said, most reported a lot of negative news - usually the bad stuff, very little good stuff.
Since I started working from home (telecommuting) - I jump right into work without turning on the TV. And after work, I typically exercise or run errands (as I no longer stop by stores on my way home from the office). So I only catch the occasional national news once in a while (few times a month), and catch the local news a few times a week - mostly for the weather reports.
I found I'm much happier and stress-free since I stopped constantly watching the news. I think there is a lot of truth to being constantly bombarded with all that negativity that it gets people stressed and depressed. I also found when talking about some issues with friends who are constantly watching some of whatever is the current "hot" issue, it seems they lose perspective because they are too close to the issue. When I hear it for the first time a few days later - I typically point out many of the "issues" really are not end-of-the-world show-stoppers that they seem to feel they are. Once I get them to stop and step back, they realized the issues really were not as bad as they initially thought based on their constant news feeds.