Other best-picture nominees are "Frost/Nixon," "Milk," "The Reader" and "Slumdog Millionaire."
As expected, Heath Ledger had a supporting-actor nomination for "The Dark Knight" on the one-year anniversary of his death from an accidental overdose of prescription drugs. But the Batman blockbuster was shut out from other top categories such as best picture and director.
"Slumdog Millionaire" lived up to its rags-to-riches theme, coming in second with 10 nominations, including a directing spot for Danny Boyle and two of the three song slots.
Pitt and real-life partner Angelina Jolie both will be going to the Oscars as nominees. Jolie had a best-actress nomination for the missing-child drama "Changeling," while Pitt is up for his role as a man born old who ages backward toward childhood, an epic tale based on an F. Scott Fitzgerald story.
The acting categories were loaded with surprises. Kate Winslet won two Golden Globes, best dramatic actress for "Revolutionary Road" and supporting actress for "The Reader." But she was nominated for lead actress at the Oscars for "The Reader" - and shut out for "Revolutionary Road."
Actors considered longshots also sneaked in, among them lead-actor nominee Richard Jenkins for "The Visitor," best-actress contender Melissa Leo for "Frozen River" and supporting-actor pick Michael Shannon for "Revolutionary Road."
Winslet reunited with "Titanic" co-star Leonardo DiCaprio for "Revolutionary Road," but he also was shut out for a nomination on that film.
Other best-actress nominees were Anne Hathaway for "Rachel Getting Married" and Meryl Streep for "Doubt." It was a record 15th nomination for Streep, who already had more Oscar nominations than any other actor.
A drama set at a Roman Catholic school, "Doubt" had four of the 20 acting nominations. Besides Streep, Philip Seymour Hoffman, Amy Adams and Viola Davis were nominated in supporting categories.
"It's divine," Davis said. "It feels like the greatest blessing in the world. It's a fulfillment of a purpose. It's a fulfillment of a dream. It's everything that you could possibly imagine it is, and not that I needed the nomination to know I was on the right path, but it certainly helps. It really does."
Joining Pitt and Jenkins in the best-actor category were Frank Langella, "Frost/Nixon"; Sean Penn, "Milk"; and Mickey Rourke, "The Wrestler."
Robert Downey Jr. - star of the year's other big superhero flick, "Iron Man" - is up against Ledger with a supporting-actor nomination for "Tropic Thunder," a rare broad comedy that crept into the acting categories.
Other supporting-acting picks include Josh Brolin for "Milk," Penelope Cruz "Vicky Cristina Barcelona" and Marisa Tomei for "The Wrestler."
"It's personal," said Brolin of his first Oscar nomination. "The movie got eight nominations, which I'm so happy about. With 'No Country,' I was just as happy, but in a different way. There was nothing personal about it. I was so happy for Javier (Bardem). Javier called me from Spain just now. He was running through the streets of Spain screaming at the top of his lungs."
Notably snubbed in the acting categories were Clint Eastwood for "Gran Torino," Sally Hawkins for "Happy-Go-Lucky" and Kristin Scott Thomas for "I've Loved You So Long."
But perhaps the biggest surprise overall was the so-so results for "The Dark Knight," which had been picking up momentum as one Hollywood trade guild after another chose it as one of the year's best films.
The largest blockbuster in years, "The Dark Knight" had eight nominations, but other than Ledger's honor, it scored only in technical categories such as cinematography, visual effects and editing.
Before his death, Ledger's reinvention of the Joker as a mad-dog anarchist already was bringing him Oscar buzz. After Ledger died on Oscar nominations day a year ago, an almost mythical aura grew around the actor, helping fuel a record $158.4 million opening weekend for "The Dark Knight" last summer.
Long viewed as the favorite, Ledger won the supporting-actor prize at the Golden Globes. If the same happens on Oscar night, Ledger would be only the second performer to receive an Oscar posthumously, following Peter Finch, the best-actor winner for 1976's "Network."
Ledger is the seventh actor to earn a posthumous nomination. Along with Finch, others include James Dean, nominated for best actor twice after his death, with 1955's "East of Eden" and 1956's "Giant."
The other actors nominated after their deaths were Spencer Tracy (1967's "Guess Who's Coming to Dinner"); Ralph Richardson (1984's "Greystoke: The Legend of Tarzan, Lord of the Apes"); Massimo Troisi (1995's "The Postman"); and Jeanne Eagels (1929's "The Letter").
Directors of all five best-picture nominees all were nominated. Along with Boyle and Fincher, the directing category includes Ron Howard for "Frost/Nixon," Gus Van Sant for "Milk" and Stephen Daldry for "The Reader."
Featuring a cast of unknowns, "Slumdog Millionaire" mixes the humorous and the horrific in a love story about an orphan from the streets of Mumbai who becomes a champion on India's version of "Who Wants to Be a Millionaire."
The film's newcomer cast was shut out in acting categories, but its 10 nominations included slots for screenplay, cinematography and musical score.
"Slumdog Millionaire" nearly became a casualty of 2008's collapse of studio arthouse divisions. Warner Independent had been set to release the film, which went into limbo after Warner Bros. shut down the specialty banner; it faced a straight-to-DVD fate until 20th Century Fox division Fox Searchlight stepped in.
So far playing in relatively narrow release, "Slumdog Millionaire" has climbed to nearly $45 million at the domestic box office, with plenty of shelf life left to make good on its modest $14 million production budget. The film dominated the Golden Globes, sweeping all four of its categories, including best drama and director.
Like "Slumdog Millionaire," "The Wrestler" presents an on-screen comeback drama, but in the form of Rourke himself. Playing a former wrestling star with one last shot at glory, Rourke returns to the promise of his early career, before his bad-boy behavior made him virtually unemployable in Hollywood.
"The Wrestler" earned Rourke the Golden Globe for dramatic actor, as well as the title-song honor for Oscar winner Bruce Springsteen. But Springsteen missed out on a song nomination for "The Wrestler."
Along with the two tunes from "Slumdog Millionaire," the third song nominated was one co-written by Peter Gabriel for the animated blockbuster "WALL-E."
The robot romance, the latest Pixar Animation blockbuster coming in as the favorite for the animated-feature Oscar, is up against the martial-arts comedy "Kung Fu Panda" and the dog tale "Bolt."
A win for the critically adored "WALL-E" would be the fourth feature-length animation Oscar for Pixar, giving the outfit behind "Ratatouille," "Finding Nemo" and "The Incredibles" half of the eight trophies since the category was added in 2001.
Oscar nominees are chosen in most categories by specific branches of the Academy of Motion Picture Arts and Sciences, such as actors, directors and writers. The academy's full membership of about 6,000 was eligible to vote for best-picture nominations and can cast ballots for the winners in all categories presented at the Oscar ceremony itself.
The 81st Oscars will be presented Feb. 22 at Hollywood's Kodak Theatre and broadcast on ABC.
While the ceremony is a month away, this year's Oscars already present a departure from previous shows: Rather than a comedian, such as past hosts Billy Crystal, Chris Rock or Jon Stewart, the emcee is Hugh Jackman, star of the "X-Men" flicks and a Tony Award winner for best actor in a musical.
Rock, the Oscar host four years ago, has some advice for Jackman about handling the crowd of nominees, most of whom go home empty-handed.
"I'll tell him what Billy told me. An hour and a half into the show, most of the audience has lost, so you have to take that into account as you go on with the show," Rock said this week at the Sundance Film Festival. "But I'm sure he'll be great, singing and dancing and doing his thing."