Late Show with David Letterman: Live from sunny Los Angeles, it's "Dick Clark's Rockin' Countdown to December 18," followed by "Casey Kasem's Countdown to Dick Clark's Rockin' Countdown to December 18." When it strikes midnight, Casey is nearly drowned in a sea of confetti. Also, Dave clarifies a statement made during "Know Your Current Events" regarding Disney's takeover of Times Square, and Third Eye Blind performs "Jumper."