* MUSIC: The third annual "Fiesta Navidad," with Mariachi Los Camperos de Nati Cano, will take place at 3 and 8 p.m. on Saturday at the Orange County Performing Arts Center in Costa Mesa. Natividad Cano's mariachis will be sharing the stage with Ballet Folklorico Ollin and Conjunto Macuilxochitl. The concert is sponsored by the Philharmonic Society of Orange County. . . . Split into two chamber orchestras, the L.A. Philharmonic plays different programs, under conductors Joseph Swensen and Jeffrey Kahane, today at 1:30 and 8 p.m., Saturday at 2 and 8 p.m. and Sunday at 2:30 p.m. at the Dorothy Chandler Pavilion in Los Angeles. . . . Jeannine Wagner conducts the Wagner Ensemble in a program called "Quilting an American Christmas," Sunday at 4 p.m. at the Westwood United Methodist Church. . . . Sunday at 6 p.m., soprano Jane Thorngren and tenor Walter MacNeil will be among the soloists at the "Messiah" Sing-along at the Lake Avenue Church in Pasadena.
* DANCE: Ballet Pacifica's production of "The Nutcracker" continues today through Sunday at 2:30 and 7:30 p.m. at the Irvine Barclay Theatre in Irvine. Different casts of principals dance at each performance. . . . Multiple casts for the San Francisco Ballet "Nutcracker" appear at the Pasadena Civic Auditorium, tonight and twice on Saturday and Sunday. . . . Up-and-coming flamenco soloists are showcased in two programs titled "Sangue Nueve," tonight through Sunday evening at the Fountain Theatre in Hollywood.
* THEATER: "La Posada Magica," writer-director Octavio Solis' play about a young girl and her family who discover the true meaning of Christmas, is touching, clever and funny at South Coast Repertory in Costa Mesa, where it continues through Christmas Eve. . . . "Show Boat," Hal Prince's new revival of the epic, landmark musical by Jerome Kern and Oscar Hammerstein II, continues at the Ahmanson Theatre in downtown Los Angeles. The play is a glowing, deeply moving American treasure.
* JAZZ: Fusion sounds are on tap this weekend at Kikuya Restaurant in Huntington Beach when keyboardist Rob Mullins welcomes saxophonist Eric Marienthal tonight, and onetime Kenny G bassist Vail Johnson leads a combo Saturday. . . . Improvisational saxophone master Lee Konitz plays tonight and Saturday with bassist Charlie Haden and pianist Brad Mehldau, and Sunday with guitarist Larry Koonse, at the Jazz Bakery. . . . Trumpeter Arturo Sandoval, a disciple of the late Dizzy Gillespie, leads a quintet tonight through Sunday at the Catalina Bar & Grill in Hollywood.
* MOVIES: "Jerry Maguire" (general release) is a satisfying, personal romantic comedy that fulfills the promise of writer-director Cameron Crowe and gives Tom Cruise, as a sports agent whose life falls apart, a chance to expand within his range. It is pleasingly idiosyncratic with terrific supporting work by Renee Zellweger, Cuba Gooding Jr. and numerous others. . . . Denzel Washington and Whitney Houston dazzle in "The Preacher's Wife" (general release), a warm, astute updating of "The Bishop's Wife" from 1947. But the film's key figure is the preacher himself, a hard-pressed inner-city minister, beautifully played by Courtney B. Vance. . . . LACMA's tribute to Jerome Kern continues tonight at 7:30 with the extremely rare "Sally" (1929), starring legendary Broadway musical comedy star Marilyn Miller, and "The Cat and the Fiddle" (1934) with Jeanette MacDonald and Ramon Novarro, directed by William K. Howard. . . . In the spirit of the holiday season, the evergreen "Meet Me in St. Louis" (1944) screens Saturday and Sunday at 11 a.m. at the Sunset 5 in West Hollywood.
* POP MUSIC: Fluf plays alternative rock tonight at the Lava Room in Costa Mesa. . . . Local rockers the Grabbers and Rule 62 play tonightat Linda's Doll Hut in Anaheim for the club's ongoing series of Christmas benefit shows. . . . Rock en espanol bands from Mexico, Colombia, Puerto Rico and other ports of call convene today at 4:30 p.m. at the Universal Amphitheatre for the "Revolucion '96" concert.
* ART: The Orange County Center for Contemporary Art's 16th annual juried exhibition, selected by Phoenix Art Museum curator David Rubin, runs through Jan. 25 at OCCCA's temporary location, 208 N. Broadway, Santa Ana. . . . With work that is so subtle, so powerful and previously so little-known, "Roy DeCarava: A Retrospective," at the Los Angeles County Museum of Art through Jan. 26, is a must-see exhibition. It's quite large, containing some 200 pictures, mostly of the daily lives of African Americans, and there isn't much sense of an artist working out his tentative ideas in the early years, then deepening. He starts out full throttle, beginning around 1950, and goes from there.
* FAMILY: The 65-member All-American Boys Chorus will present "Sounds of Christmas," a holiday concert of seasonal favorites, at the La Mirada Theatre on Sunday at 4 p.m.