Marvel's Official Thor Movie Hub has confirmed the rumors that Pirates of the Caribbean's Stellan Skarsgård has joined the cast, but they don't specify which role the Swedish actor will play. The IMDB and the Marvel Movie Wiki, however, both claim Skarsgård will portray Professor Andrew Ford.

Meanwhile, The Hollywood Reporter says that Oscar nominee Adriana Barraza (Babel) will play an unspecified human character. We suspect her role is that of the previously rumored Isabel Alvarez, a New Mexico resident in her 50's-60's who was described as a "sweet small town gal who has lived her whole life in the same little town where she grew up. She's faced plenty of ups and downs in her many years but has everything she's ever wanted or needed in the small slice of Americana, family, friends and the best little restaurant in town."

"Thor" spans the Marvel Universe; from present day Earth to the realm of Asgard. At the center of the story is The Mighty Thor, a powerful but arrogant warrior whose reckless actions reignite an ancient war. Thor is cast down to Earth and forced to live among humans as punishment. Once here, Thor learns what it takes to be a true hero when the most dangerous villain of his world sends the darkest forces of Asgard to invade Earth.

Chris Hemsworth (Star Trek) plays the title role. The cast also includes Anthony Hopkins as Odin, Natalie Portman as Jane Foster, Tom Hiddleston as Loki, Samuel L. Jackson as Nick Fury, Ray Stevenson as Volstagg, Stuart Townsend as Fandral, Tadanobu Asano as Hogun the Grim, Idris Elba as Heimdall, Rene Russo as Frigga, Jaimie Alexander as Sif, Kat Dennings as Darcy, Joseph Gatt, and Colm Feore in an unspecified villain role.

"Thor" is now slated for a May 6, 2011 release.