I find that "the news" is what is creating those bubbles. The more you read the nytimes, or watch fox, the more you lock into that particular bubble mindset.
NYT? Only if you consider "what's actually happening" or "reality" to be a bubble. I see both liberal and conservative viewpoints in the NYT all the time.
Reality does have a stubborn liberal bias, after all.
That said, NYT is equally driven by sensationalism, in the "If it bleeds, it leads" sense.