Mike,

I would put the era of “objectivity” as lasting from the rise of the first radio networks in the 1920s, until the successive arrival, beginning in the late 1980s and continuing to this day, of Rush, Fox News, Drudge, the Blogosphere and its spin-offs (such as PJTV), but you’re right–we are moving back to the pre-WWII-forms of openly biased media. Though during the transition phase we’re in, not all publishers or journalists are willing to announce their biases, even though it’s obvious to most readers where various journalistic outlets stand.

I tried to provide snapshots of both the birth of mass media, and the birth of its successor forms in my “Atlas Mugged” article a couple of years ago.