Originally we got word that Saoirse Ronan was up for the role of Wanda Maximoff (aka, Scarlet Witch) for The Avengers: Age of Ultron. Now it seems she may have passed as rumors are out that Elizabeth Olsen (Martha Marcy May Marlene) is now under consideration for the role. If Olsen gets it, she will most likely be opposite Aaron Taylor-Johnson (Kick-Ass) who is the frontrunner to play Petro Maximoff (aka, Quicksilver).
Other projects that Elizabeth Olsen has on deck right now is Spike Lee's adaptation of Oldboy and the new Godzilla reboot which oddly enough also stars Aaron Taylor-Johnson.
As you might know, Petro and Wanda are the twin children of Magneto from X-Men. Seeing that X-Men is not a Disney owned franchise and is owned by Fox, the characters will not be tied into Magneto for The Avengers. Not unless they want to pay a price to even mention the character. I suppose these characters will just come out of nowhere.
Quicksilver has the power of super speed while Scarlet Witch can alter probability and reality.
I think Elizabeth Olsen would be an interesting choice for Scarlet Witch but not necessarily a bad one. It will be interesting to see how this one plays out. Especially since they haven't officially signed Aaron Taylor-Johnson on to play her counterpart. That could still change.
The Avengers: Age of Ultron is set to hit theaters on May 1, 2015.