The Associated Press

CNN has canceled its long-running Talkback Live, that has originated from the Atlanta mall outside of the CNN offices. The show ran 3-4 p.m. Monday-Friday.

The show has been replaced this week with an expanded, three-hour edition of Live From, which has aired 1-3 p.m. The news show features Kyra Phillips and Miles O'Brien reporting from the scene of the day's big story.

Talkback Live, with Arthel Neville as the current host, has been on CNN for nine years. The final telecast was Friday. Neville is expected to stay at CNN.

The somewhat awkward format made it a favorite target of critics, but it drew solid ratings for CNN during the day.

"As we face mounting tensions abroad and growing threats here at home, it makes a lot of sense to program this network in a way that both meets the demands of our viewers and the news environment in which we find ourselves," said Teya Ryan, CNN's executive vice president and general manager.

Dave's subs: David Letterman hasn't fully recovered from the shingles, so a week of guest hosts have been lined up for CBS' Late Show (11:35 p.m., Channels 12, 7).

Vince Vaughn will sub tonight and interview guests Angie Harmon, author and sex expert Sue Johanson and Paul Simon.

Elvis Costello will host Wednesday, followed by Will Ferrell on Thursday. Friday's guest host has not been announced.

When Letterman missed shows Feb. 26-28, Bruce Willis, John McEnroe and Regis Philbin sat in for him. The Late Show aired reruns last week, a break that had been scheduled before his illness.

"Dave's condition continues to improve and his overall health is excellent, but a complete recovery will require some additional time. Dave's principal treatment at this point is rest," said Letterman's physician, Lou Arrone.

Radio highlight: The works of Rachel Portman, Louise Duval, Ruth Crawford Seeger, Conni Ellisor and other female composers will be featured on the two-hour special, Instrumental Women: On Record, at 8 p.m. today on WGUC-FM (90.9).

Rowling on `Simpsons': When Harry Potter fan Lisa Simpson meets Potter creator J.K. Rowling in an episode of The Simpsons, the author will provide her own voice.

Don Payne, a producer of the Fox series, tells London's Sun newspaper that the Simpson family will travel to England to track down a woman with whom Grandpa had a wartime fling. They run into Rowling in a bookstore.

Homer and his family also bring bad luck to Lord of the Rings star Ian McKellen when they see him in Macbeth.

Leno line: Says Tonight Show host Jay Leno: "Fox should combine two reality shows into one series and call it When Animals Attack Those Idiots on Married by America.

TV today: Teens explore the tensions between Americans and Arabs when Jim, 16, from North Carolina, and Abdulrahman, 15, from Jordan, spend time in each other's country on A Walk in Your Shoes (9 p.m. on Noggin, Time Warner digital Channel 124).

• Mutual of Omaha's Wild Kingdom premieres "Meerkats Unmasked" (8 p.m., Animal Planet).

• Take a TV trip up the road to Dayton for a trio of specials on Channels 16 and 14 for Memories of Dayton (8 p.m.), Let's Go Down to Rikes (9 p.m.) and When Dayton Went to War: Memories of the Homefront (10 p.m.).

• The Family (10 p.m., Channels 9, 2) gets its first etiquette lesson before playing polo - on donkeys.

Talk shows: Today's guests:

Live with Regis and Kelly (9 a.m., Channel 9): Jennifer Love Hewitt, Michelle Branch.

Wayne Brady (10 a.m., Channel 9): Nia Vardalos, Dave Coulier, Roselyn Sanchez, Busta Rhymes.

The View (11 a.m., Channel 9): Geri Halliwell, Montel Williams.

Caroline Rhea (3 p.m., Channel 19): Joshua Jackson, Tamyra Gray.

John Kiesewetter and TV Data contributed to this report.