Based on the series premiere, Joey Tribbiani is missing a few viewers along with his "Friends."

An estimated 18.6 million people watched the first episode of "Joey" on Thursday, the spinoff of "Friends" that NBC was counting on to keep its Thursday night lineup strong, according to Nielsen Media Research.

That's fewer viewers than any original episode of Matt LeBlanc's old series drew last season.

NBC notes that "Joey" gathered the largest audience among the advertiser-friendly 18-to-49-year-old age group of any entertainment show since May. It was also the best-rated 8 p.m. comedy premiere for NBC in 14 years.

Yet given that NBC promoted the series heavily during the Olympics and that its chief Thursday competition, "Survivor," hasn't started the season yet, that number was expected to have been higher, said Marc Berman, a TV analyst for Media Week Online.

"I can't imagine they're all there [at NBC] jumping for joy," he said. "Joey" should settle in to being "a respectable hit, but it won't be a breakout hit." The ratings compare to last season's premiere of CBS's "Two and a Half Men," which drew 18.4 million viewers.

Looking at Thursday night's numbers, Donald Trump's job security may not be that much better than the ambitious contestants he's putting on the firing line. The debut of "The Apprentice" for its second season was seen by 14.1 million people, Nielsen said. That's the lowest number yet for the business game, down from the 20.7 million average for the first season and the 18.5 million who saw the first-season premiere.

"The Apprentice" went up against the first game of the National Football League season, stiffer competition than usual on ABC. CBS's "CSI: Crime Scene Investigation" was airing a rerun at the same time. (David Bauder, Associated Press)

'Happy Days' again for ABC

To mark the 30th anniversary of one of its best-loved sitcoms, ABC is holding a reunion for the "Happy Days" cast -- even Chuck.

The reunion show, set for later this season, will bring together nearly all the cast, including Ron Howard, Henry Winkler, Tom Bosley, Marion Ross, Anson Williams, Don Most and Erin Moran. Gavin O'Herlihy and Randolph Roberts, who played Richie's older brother Chuck during the show's first two seasons, will also be on hand, as will series creator Garry Marshall.

Whether Marshall will explain what happened to Chuck -- who was never heard, seen nor even mentioned after the show's second season -- remains to be seen.

In addition to the original cast, Scott "Chachi" Baio, Ted "Roger Phillips" McGinley, Penny "Laverne" Marshall, Cindy "Shirley" Williams, Pat "Arnold" Morita and others who played recurring or regular roles during "Happy Days' " 11-year run will also appear on the special. (Zap2it.com)

Kidder on 'Smallville'

As The WB drama "Smallville" prepares to welcome the character of Lois Lane into its mythology, the most popular and familiar Lois Lane is ready to make a cameo. Margot Kidder, co-star of the last four "Superman" movies, is taking flight to The WB to visit with Tom Welling's kryptonite-hating superhero.

Kidder will play Bridgette Crosby, emissary to Dr. Swann, a cute twist, because Swann has been played by Kidder's big-screen super-love Christopher Reeve. The character will first appear in the show's season premiere on Sept. 22 and will return for the sixth episode. Coincidentally, the season premiere will also feature the first appearance by Erica Durance as Lois Lane.

Adding to the fun will be the reunion of Kidder and "Smallville" co-star Annette O'Toole, who played Lana Lang in "Superman III." On "Smallville," to bring things full circle, Lana Lang is played by Kristin Kreuk. (Zap2it.com)

WPTT radio hosts switch

Two WPTT-AM (1360) talk hosts will switch places starting Monday. Afternoon host Doug Hoerth moves to morning drive (7 to 10 a.m.). Morning host Jerry Bowyer will move to afternoons (3 to 6 p.m.), where his show will focus on events and newsmakers of the day.

WPTT program director John Poister said he had been thinking about making the change for a while. The station experimented with the swap over the summer, using Hoerth and Bowyer as fill-in hosts when the other was on vacation. Audience feedback was good, Poister noted. (Adrian McCoy, Pittsburgh Post-Gazette)

Voter registration

Infinity Radio Pittsburgh is joining other Infinity stations across the country today for "Infinity Registers America -- Your Voice Counts," a one-day voter registration drive.

During the day, listeners to local Infinity stations KDKA-AM (1020), WDSY-FM (107.9), WZPT-FM (100.7) and WRKZ-FM (93.7) will hear public service announcements directing them to the stations' Web sites, which will have detailed instructions on the registration process.

There will also be local registration sites: KDKA will be at Bruegger's Bagels, Market Square, from 7 to 9 a.m. and 11:30 a.m. to 1:30 p.m., and at Hard Rock Cafe, Station Square, from 11:30 a.m. to 1:30 p.m.; WDSY will be at Bruegger's, Library Road in Bethel Park, from 11:30 a.m. to 1:30 p.m.; WZPT will be at Bruegger's, East Carson Street, South Side, from 11:30 a.m. to 1:30 p.m; and WRKZ will be at Bruegger's, Grant Street, Downtown, from 11:30 a.m. to 1:30 p.m. (A.M.)

Borg leaving KDKA

Jessica Borg, a KDKA reporter and the anchor of WNPA's 10 p.m. news on the weekends, is leaving the station for a job at WPVI, the ABC affiliate in Philadelphia. She'll anchor weekend mornings and report three days a week.

"KDKA has offered me some wonderful professional opportunities, but this was an opportunity I couldn't pass up," she said, noting that she'll be closer to family in New York.

Borg joined KDKA in May 2000. Her last day at the station will be Friday. No replacement anchor for WNPA's weekend newscast has been named. Several KDKA female anchors have maternity leaves coming (Kelli Olexia and Kristine Sorensen; Jennifer Antkowiak is currently on maternity leave). Different faces are likely to pop up in that slot in the coming months. (Rob Owen, Post-Gazette TV editor)