I don't mind that kind of bias, if your 2x2 matrix was right -- that each of them reports everything good about their side and everything bad about the other side. If that were true, you could sum them up and have a pretty balanced total news source.

The problem with Fox News and CNN is the biased attitude. They report everything good as amazing and everything bad as horrible. The anchors are "performing" the news, telling you with their tone, body language and vocal intonations how disgusted you should be or how much you should be rejoicing. This phenomenon has infiltrated the NYT and WSJ as well, and I've stopped reading both.