Twain's new album, "Up!," has been No. 1 in each of its three weeks in release. Keith will sign a duet with Nelson.
The show will also feature a musical performance by Kelly Osbourne, who -- along with the rest of The Osbournes -- will host the telecast over ABC on Jan. 13.
Organizers had already announced that country superstar Tim McGraw and pop icon Elton John will open the show with a duet on "Tiny Dancer" -- one of John's early hits which has become a popular part of McGraw's repertoire.
TOM SELLECK SPEAKS OF WAR
Actor Tom Selleck, like so many others in Hollywood, has something to say about the prospect of war in Iraq.
In an interview to promote his upcoming TNT movie "Monte Walsh," Selleck was asked whether he agreed with the statement issued this week by a group of more than 100 Hollywood celebrities urging President George W. Bush not to mount a preemptive war.
"I don't think anyone should jump the gun at this moment," said Selleck. "We need to give our leaders the benefit of the doubt, but maintain our vigilance as citizens."
Selleck was concerned about the prospect that the war on terrorism is eroding civil liberties for Americans.
"It's easy to solve a lot of these problems if we don't care about our civil liberties," he said. "It's easier to be safe and not free than it is to be free and not safe."
The star of "Magnum, P.I.," "Three Men and a Baby" and "Quigley Down Under" suggested that legislation limiting freedom should include sunset clauses, giving lawmakers a chance to do away with provisions that don't work as intended.
ARTHUR HILLER HEADS FOR GREEK FESTIVAL
Director Arthur Hiller will be the guest of honor this weekend at the American Comedy Film Festival in Athens, Greece.
A former president of the Academy of Motion Picture Arts and Sciences (1993-97), Hiller is scheduled to attend the festival from Friday through Dec. 19. His appearance is sponsored by the academy's Visiting Artists Program. The festival is organized by the United States Embassy in conjunction with the Greek Film Archives.
Hiller was nominated for a directing Oscar in 1970 for "Love Story." In 2001, he received the Academy's Jean Hersholt Humanitarian Award.
At the festival, he will introduce a screening of "Silver Streak," one of five of his films that are being shown. The others are "The Hospital," "The In-Laws," "The Out-of-Towners" and "Outrageous Fortune."
In all, 22 American comedies will be screened at the festival.
BOY BAND BOSS BRANCHES OUT
Louis Pearlman -- widely credited with engineering the success of boy bands 'NSYNC and Backstreet Boys -- is getting into the TV and movie business.
Pearlman has joined up with Steve Austin's Tag Entertainment to form Tag Studios, with plans calling for the new outfit to produce theatrical films and TV shows specializing in family oriented entertainment with an emphasis on music.
According to a press release, the new company has four features in development and two in pre-production. Pearlman and Austin hope to produce six family films each year.
"The music business has been very good to me," said Pearlman, "and it is my intention to parlay that experience, knowledge and know-how into building a strong, viable film and television operation."
The studio's first production will be "Supercross," described as the story of a working class family trying to give teenage son a chance to race Supercross. Plans call for the studio's second production to be a live-action version of "Little Red Riding Hood."
DOOGIE GOES TO 'BOOMTOWN'
Neil Patrick Harris will guest-star on NBC's "Boomtown" next month, playing a filmmaker who pays vagrants to fight each other for the camera.
Harris ("Doogie Howser, M.D.," "Starship Troopers") will appear in the Jan. 5 episode, as an ambitious amateur filmmaker who gets involved in producing black-market videotapes of brutal battles between homeless men. An investigation into the murder of a homeless man leads investigators to Harris' character.
Harris is set to star on Broadway as The Master of Ceremonies in "Cabaret."
DICK VAN DYKE HEADS FOR TV OPERATING ROOM
In an episode scheduled for Jan. 23, Hughley will play the brother of Turk (Donald Faison), and Van Dyke will play an old friend of Dr. Kelso's (Ken Jenkins).
The storyline calls for Van Dyke's character, a veteran doctor, to set out to give a younger doctor a lesson in "old school" medicine, but the older doctor ends up coming to grips with his own lack of knowledge about up-to-date medicine.