Everybody thinks that they, personally, are fair and balanced. People who don't are exceptionally intellectual and/or reflective. Don't believe me? Try telling a friend that you think that they are unfair and judgmental. See how far you get.
Therefore it's logical that when someone hears an opinion that they agree with, they will most likely think that it to is fair and balanced, and likewise whomever said it. Otherwise the cognitive dissonance in holding said opinion would be too great.
And herein lies the problem with the complaints that liberals make about Fox News claiming to be Fair and Balanced: they're preaching to the choir. Only people who disagree with Fox News will disagree w/ their slogan, while people who like Fox are going to defend them.
And I say this as one who tends towards the liberal and thinks Fox News is full of sh!t.
Btw if you think the current media situation is untenable and represents the demise of democracy as we know it, you'd do well to read this: http://www.nydailynews.com/opinions/2009/10/26/2009-10-26_unbalanced_even_for_abe.html. I'd say we're slightly better off now from a media perspective and that our democracy has survived just fine in the last 150 years ...