Rene Russo hasn't made a movie since 2005's Yours, Mine and Ours, which definitely did not help her career. You may know her from a couple classic films such as Lethal Weapon 3 & 4 and Get Shorty.
From out of nowhere she is cast in Marvel's upcoming comic book film Thor. Russo is set to play Frigga who is the wife of the Norse god Odin -- which is being played by the great Anthony Hopkins -- and stepmother of Thor.
I think Russo is a very good actress, and will do a fine job playing this part. Here is a more detailed explanation of the character Frigga, and her role in the Marvel Universe:
An Asgardian, she is the Queen of Asgard, wife to Odin, step mother to Thor and foster mother to Loki. Frigga had supervised the location and training of the apprentices to the Celestials, the Young Gods. Because of the events of Ragnarok, Frigga is believed to have suffered the same fate as the rest of the Asgardians.