I don't know about CNN, MSNBC, or Aljazeera, but Fox News admitted to fabricating stories and lying in court (bizarrely, they won the right to lie and call it news in said same court).

http://ceasespin.org/ceasespin_blog/ceasespin_blogger_files/... http://digg.com/news/entertainment/the_daily_show_fox_news_l...

(I'm for totally ignoring CNN, MSNBC, and Aljazeera as well if they admit to intentionally misleading the public.)

Bias isn't bit-field. It's perfectly possible for all news to be biased and for Fox to be in a terrible, egregious class of its own.