The Screen Actors Guild on Thursday unveiled nominations for its widely watched film awards, giving key nods to three films including Up in the Air and capping a busy week of honors from industry groups.

In the past five days, critics and others across the United States have named best films, top 10 lists and nominations for upcoming honors such as the Golden Globe Awards -- all leading to the world's top movie awards, the Oscars, in March.

Hollywood watchers are focusing on several movies in the awards sweepstakes including Quentin Tarantino's war fantasy Inglourious Basterds, urban drama Precious: Based on the Novel 'Push' by Sapphire, Iraq war movie The Hurt Locker, mid-life crisis tale Up In the Air and adventure Avatar.

It's thrilling and gratifying and pretty extraordinary from this particular filmmaker's perspective, said Hurt Locker director Kathryn Bigelow about her movie's success.

Three films, Up in the Air, Inglourious Basterds, and Precious earned three nominations apiece for Screen Actors Guild (SAG) awards with Basterds and Precious among nominees for best ensemble cast, SAG's top honor.

Joining them were the stars of the musical Nine, including Penelope Cruz and Daniel Day-Lewis, as well as the actors in The Hurt Locker and An Education.

Up in the Air, starring George Clooney as a corporate hatchet man, earned three nominations for Clooney as best actor and Vera Farmiga and Anna Kendrick as best supporting actress.

AIR UP IN SMOKE?

While it failed to make SAG's nominees for cast -- believed to be a bad sign because actors are the largest voting block at Oscar-giver The Academy of Motion Picture Arts and Sciences -- Up in the Air has led many critics' lists and been an early front-runner. And pundits say not to count it out yet.

It's all about momentum, said veteran award-watcher Anne Thompson, whose blog Thompson on Hollywood, appears on film website IndieWire. I suspect it may remain in the top five, but it could have peaked in the race to No. 1.

David Poland, who runs website Movie City News, said the big change this week has been the smashing critical success and box office potential of director James Cameron's Avatar.

It's a very well-liked movie and a movie that's going to do an unusually good amount of (box office), which the Academy likes to see, Poland said. 'Avatar' has changed the game.

In SAG's other key film categories, Clooney will be joined in the best actor race by Jeff Bridges in Crazy Heart, Colin Firth in A Single Man, Morgan Freeman for Invictus and Jeremy Renner in The Hurt Locker.

The five nominees for best actress were Sandra Bullock for football movie The Blind Side, Helen Mirren in The Last Station, Carey Mulligan for An Education, newcomer Gabourey Sidibe in Precious and Meryl Streep in Julie & Julia.

Joining Farmiga and Kendrick in the race for supporting actress will be Penelope Cruz in Nine, Diane Kruger for Inglourious Basterds and comic actress Mo'Nique, who took on a dramatic role playing an abusive mother in Precious.

SAG's supporting actor race pits Matt Damon in Invictus against Woody Harrelson in The Messenger, Christopher Plummer for The Last Station, Stanley Tucci in The Lovely Bones and Christoph Waltz with Inglourious Basterds.

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