The freedom of expression does extend to the written form. The Court has consistently, if not in every single case, come down on that side. However, it is a fragile right, capable of being chipped away at. The Supreme Court has immense power and it is in the realm of possiblity that some day those rights could be severely limited. But yes, at this point, we have broad legal freedom of expression.
That, however, does not mean that it is a fully exercised freedom.
The media and the newspapers censor themselves daily for a variety of reasons and I would guess that Americans are no better informed (and possibly less so) than many other countries.
It is probably more considered that people will make their judgments based on whatever coloring the particular medium (including print) uses to paint the picture, lol. It appears more and more Americans are going outside of American media and press to get a more complete picture. Doesn't mean they are getting the complete picture elsewhere, just that they are getting details we are often not given here.
I would also hazard a guess that this is a right valued more in spirit than in reality by many Americans.