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.
"This is a great honor for the movie, and I'm especially happy for David Fincher, for without him there would be no Ben Button," Pitt said in a statement.
Jolie also had gushing words for her director, "Changeling" filmmaker Clint Eastwood.
"Working with Clint Eastwood was a reward in itself that will last me a lifetime," Jolie, a supporting-actress Oscar winner for "Girl, Interrupted," said in a statement. "To receive a nomination from the academy on top of that is a privilege beyond any expectation."
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," as was Leonardo DiCaprio, who reunited with his "Titanic" co-star for the film.
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."
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," said Davis, who plays the mother of an altar boy who may have been abused by a priest. "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."
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, a co-star in last year's Oscar champ, "No Country for Old Men," who plays Dan White, the man who gunned down gay-rights pioneer Harvey Milk in "Milk."
"The movie got eight nominations, which I'm so happy about," Brolin said. "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," Golden Globe winner Sally Hawkins for "Happy-Go-Lucky" and Kristin Scott Thomas for "I've Loved You So Long."
But 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.