Who would have guessed that Katie Couric was really a night person?
With the numbers now in, Monday's job swap between the "Today" host and her "Tonight Show" counterpart, Jay Leno, proved a bonanza for Couric and something of a letdown for Leno.
The a.m. sweetheart -- revealing well-toned arms in a sleeveless dress that also displayed her great legs -- drew 42 percent more viewers than usually tune in for Leno's late-night antics.
Preliminary ratings for her Monday stint were a 7.1 and a 17 share, the highest numbers for "Tonight" since May 2000, according to Nielsen Media Research.
At the same time, Monday ratings for "Today" were barely affected by the appearance of Leno, 53, who displayed neither arms nor legs, just a great deal of self-consciousness as he kicked off the show.
Leno delivered a modest 9 percent ratings spike for "Today," though while Couric had help from the highly entertaining Mike Myers, "American Idol" judge Simon Cowell and British pop star Robbie Williams (to say nothing of a surprise visit by Dr. Phil McGraw), Leno had to contend with the far more serious Secretary of State Colin Powell and former New York Mayor Rudolph Giuliani.
Couric, 46, also made a slight dent in the ratings for rival CBS's "Late Show with David Letterman." Dave, 56, averaged a 4.0 overnight rating, down from 4.8 a week earlier.
In a statement, NBC Entertainment President Jeff Zucker said of the job swap, which was Couric's idea: "This was really well promoted, really well publicized. This is what we hoped for. We're thrilled."
New York's Daily News reports that the gimmick will likely be repeated next year.