Jay Leno, Kevin Smith Lend a Thumb

The thumbs-up you're about to see is not Roger Ebert's.

Jay Leno and Kevin Smith have been tapped to sit in for the Ebert & Roeper cohost while he continues to recover from the cancer surgery he had last month at a Chicago hospital.

"We're honored that Jay has accepted our invitation," Chicago Tribune critic Richard Roeper told the Chicago Sun-Times, where Ebert has been a resident film critic since 1967. "He has been a great friend of Siskel & Ebert and Ebert & Roeper over the years. Whenever Roger and I guest on The Tonight Show, the producers always ask us to arrive early so Jay can debate movies with us backstage."

Leno will be flexing his hitchhiking muscle on the Aug. 5-6 episode of Ebert & Roeper, where he'll be asked to pan or sing the praises of Talladega Nights: The Ballad of Ricky Bobby, Miami Vice, Little Miss Sunshine, The Night Listener and Shadowboxer, according to the Hollywood Reporter.

"Jay watches movies with a critic's eye and he has a lot of interesting insights about movies that he's shared with me over the years," Roeper said. "Now he'll get a chance to share new insights about some big summer movies in the balcony setting."

So that Leno won't have to take any time off from monologues and "Headlines," Roeper will fly out to Los Angeles to tape the episode.

Smith announced his latest gig Tuesday on his View Askewniverse Website.

"Kind of a cool honor, I feel," the Clerks II auteur wrote. He seemed to be under the impression, however, that he would be passing judgment on Miami Vice and Talladega Nights when he cohosts the Aug. 12-13 show, so?here's hoping he gets the one he's really hoping for, World Trade Center.

Other celebrity guest hosts will reportedly join Roeper in the future, as well.

Ebert, who is currently recuperating at Chicago's Northwestern Memorial Hospital, isn't going to let his thumb relax for long, though.

"Don?t get too used to these guest cohosts because I?ll be back in the balcony before you know it," the Pulitzer Prize-winning critic said in a statement on his Website.

The 64-year-old writer and TV personality had a cancerous growth removed from his salivary gland June 16 but was back in the hospital July 2 for an emergency procedure to repair a burst blood vessel near the site of the first surgery.

This is not the first time he has been plagued by this ailment, either. Ebert underwent surgery for papillary thyroid cancer in February of 2002 and then had two surgeries on his salivary gland the following year, as well as four weeks of radiation treatment. All without missing a step on the movie beat.

"This is known as a slow-growing and persistent cancer," Ebert told the Sun-Times. "You live with it."

Roeper is also looking forward to having their show's two title characters back in the balcony.

"Roger is a fighter and I have every confidence and hope that he has thousands of movie reviews ahead of him," he said. "Led of course by his wife, Chaz, he has an amazing circle of family and friends surrounding him with love and support. I also want to express gratitude to the many fans across the country who have already sent their best wishes."

According to Ebert's family, doctors are optimistic about his condition.

"Roger is improving each day and continues on his road to recovery," Chaz Ebert said in a statement. "He's been through a lot and needs more time to recuperate?Roger will return to his seat in the balcony in the near future, and I ask that you continue to send healing thoughts his way."

Ebert's original TV partner, Gene Siskel, died of complications from a brain tumor in 1999.