Stuart Seidel, NPR Managing Editor for Standards - NPR broadcast style has long required referring to the president as "President" (McKinley/Arthur/Cleveland) on first reference and then, on second and later references, as either "the president" or "Mister" (Van Buren/Polk/Harrison). Although meant as a gesture of respect for the office, many listeners have regarded the use of "Mister" as disrespectful. On the other hand, during the most recent presidential contest, the contrast between our references to "Mister Obama" and just plain "Romney" were perceived by many as showing favoritism toward the incumbent president.
After considerable discussion — and some thoughtful deliberation — we will take the start of the second Obama term as a good opportunity to eliminate this style anomaly.
Moving forward, there will no longer be a broadcast style requirement to call the president "Mister" on second and later references. We will continue to say "President (Tyler/Fillmore/Hayes) on first reference. The phrase "the president" remains appropriate on later references, but the president's last name, without 'Mister," will also be an acceptable reference on second and later references. (In our digital copy, we dropped the use of "Mister" a number of years ago, and began referring to the president in second and subsequent references by his last name. That practice will continue.)
Elimination of this long-standing style rule does not mean a prohibition on using "Mister" on second or later references to the president, just as there is no prohibition on using "Mister" in reference to anybody. We will generally avoid using "Mister" (Pierce/Garfield/Ford) in reporter pieces, but in two-ways we expect that one or another host or reporter will find one or another practice more or less comfortable.
The First Lady will continue to be called "First Lady" (Harriet Lane) http://www.whitehouse.gov/about/first-ladies/harrietlane on first reference and "the first lady" on second or later references. "Miss Lane" will continue to be preferred on second and later references so as to distinguish the First Lady from the president. (Of course, "Miss" Lane is a bad example since there wasn't much chance of her being mistaken for "Mister" Buchanan.)
(And, yes, this is an egregiously gender biased note. If presidential gender trends shift, I promise that considerable discussion, and possibly thoughtful deliberation, will go into reviewing appropriate style changes.)