My favorite take on ABC's Nightline fiasco, from today's USA Today:

"Andy Rooney may weigh in on news vs. entertainment on Sunday's 60 Minutes. He says a poll he conducted revealed that Nightline and 60 Minutes viewers are 94% smarter than those who watch late-night comedy. Because they're so smart, they have more money to spend on the products that are advertised.

"Rooney says his poll also found that most who watch late-night comedy 'don't have to get up in the morning because they don't have jobs and therefore they don't have any money to pay for anything advertised in the commercials.'"

http://www.usatoday.com/usatonline/20020307/3920130s.htm

Also, a useful, though speculation-heavy, breakdown of the Leno-Letterman duel in the WSJ:
http://online.wsj.com/article_email/0,,SB1015455127365888880,00.html