"Survivor" host Jeff Probst gushed with praise for Cirie Fields, 35, a registered nurse from Walterboro, S.C., who graduated from St. Francis Nursing School in New Castle.

Speaking in a conference call yesterday about "Survivor: Panama -- Exile Island," which premieres at 8 p.m. Thursday on CBS, Probst said that Fields will be "one of the top five most popular Survivors ever. She represents every person who sits on their couch and says, 'I could do that,' and she delivers and is just dynamite. People will absolutely adore her." Sounds as if she'll be around for a while.

Probst singled out another contestant who he thought would be extraordinarily popular: Shane Powers, 35, of Los Angeles, owner of an entertainment marketing company. Probst said that Powers, who smoked three packs of cigarettes a day, quit cold-turkey when he arrived for "Survivor" and then asked himself, "What have I gotten myself into?"

Other players Probst says to watch: Terry Deitz, 46, an airline pilot from Simsbury, Conn.; Tina Scheer, 45, a "lumberjill" from Hayward, Wis., whose son died a week before she was supposed to take part in "Survivor: Guatemala"; Aras Baskauskas, 24, a yoga instructor from Santa Monica, Calif.; Dan Barry, 52, of South Hadley, Mass., a retired astronaut; and Misty Giles, 24, an engineer from Dallas.

In episode one, the 16 castaways will be divided for the first time into tribes of four: older men, older women, younger men and younger women. The four tribes will become two during the second episode, and Probst said it would be interesting to see which bonds stick from the original tribes.

On each episode, at least one "Survivor" will be banished to "Exile Island" miles away from camp. Probst declined to say how it would be decided who would be exiled.

But there's a new twist this season, and maybe a reason to want to be exiled. Somewhere on Exile Island, there's a hidden Immunity Idol that can be used even after a tribal council's vote. Probst said that if the person who is voted out possesses the Immunity Idol, the player who receives the next number of votes will get the boot.

Probst posed a couple of scenarios: What if a person pretended to have the Immunity Idol, didn't, and used this bluff to stay in the game? Or what if a person had the Immunity Idol, kept the information secret, and used it to vote out a rival? He promised some surprising ramifications.

Exile Island has "maybe fire, maybe water," but no shelter, and Probst laid out the possibility that many of the players will be sleeping in the rain since the show was filmed during Panama's rainy season.

Probst said this is one of the most fun seasons of "Survivor," even though on the whole the players are probably the most "introspective" group the show has ever had.

When asked who the best "Survivor" player ever was, Probst answered that he thought it would be Tom Westman of "Survivor: Palau," the Type-A New York City firefighter who had a huge target on him and won the game by a 6-1 vote.

Who was the worst player ever? Probst diplomatically declined to say, but he did describe the most bone-headed single decision ever: in "Survivor: All-Stars," when Lex van den Berghe trusted Rob Mariano and didn't vote out Beaver County's Amber Brkich, who ended up winning the $1 million.