Experts are now chiming in on who they think will win.
Entertainment Weekly's Los Angeles bureau chief Sean Smith shared his Oscar predictions with Early Show co-anchor Julie Chen.
"Who's going home with an Oscar this Sunday?" Chen asked.
Best Actor Nominees: Richard Jenkins for "The Visitor," Frank Langella for "Frost/Nixon," Sean Penn for "Milk," Brad Pitt for "The Curious Case of Benjamin Button," and Mickey Rourke for "The Wrestler."
"Who should win and who will win?" Chen asked.
"Who will win is probably Sean Penn for 'Milk,' although it's a tight race between him and Mickey Rourke. It could go to Mickey, but I'm feeling it will go to Sean," Smith said.
"Who should it go to?" Chen asked.
"I think it should go to Sean. I think that's an incredible performance. Anybody who knows Sean Penn, they know he's nothing like that character, nothing," he said.
Best Supporting Actor Nominees: Josh Brolin for "Milk," Robert Downey Jr. for "Tropic Thunder," Philip Seymour Hoffman for "Doubt," Heath Ledger for "The Dark Knight" and Michael Shannon for "Revolutionary Road."
"Who should win, who will win?" Chen asked.
"I think Heath Ledger should win. And I think Heath Ledger will win. It's really extraordinary, though, because if he wins, it is only the second time that someone who - an actor who has died has won an Oscar after they've died. The first was Peter Finch for 'Network.' It's rare for an actor who is deceased to win, but that performance is so indelible. Even if he were alive, I think he'd win. A lot of people are talking about how it's a sentimental win. I don't think so. I think if he were alive, he'd still win," Smith said.
"If he wins, who will accept for him?" Chen asked.
"His family, which will be a tear-jerker. His family will accept it. I think his parents and maybe his sister," Smith said.
Best Actress Nominees: Anne Hathaway for "Rachel Getting Married," Angelina Jolie for "Changeling," Melissa Leo for "The River," Meryl Streep for "Doubt," and Kate Winslet for "The Reader."
"Who should and will win?" asked Chen.
"Kate Winslet for 'The Reader.' She also did 'Revolutionary Road,' which she isn't nominated for this year. She's at the peak of her beauty and her power and she's been nominated six times; she's never won. I think she's going to win and it should go to her. Although Meryl is hot on her heels, she has won two. The last time she won an Oscar, Kate Winslet was 8."
Streep has won two Oscars, for "Sophie's Choice" and "Kramer vs. Kramer."
Best Supporting Actress Nominees: Amy Adams for "Doubt," Penelope Cruz for "Vicky Cristina Barcelona," Viola Davis for "Doubt," Taraji P. Henson for "The Curious Case of Benjamin Button," Marisa Tomei for "The Wrestler."
"Who should and will win?" Chen asked.
"I think who will win is probably Penelope Cruz," Smith said. "I think Viola Davis should win. Ten minutes in 'Doubt,' it's incredible. She has this one scene that is heart breaking. I think Penelope Cruz, who has been nominated before. She's really fun."
"Who's going to take home best picture?" Chen asked.
"'Slumdog Millionaire.' You can bet on it. You can bet your 401(k) on it," Smith said.