We brought you a report a couple of weeks ago about Michael Fassbender (Inglourious Basterds) having to decide whether he should play Erik Lehnsherr / Magneto in Matthew Vaughn‘s upcoming X-Men: First Class for 20th Century Fox, or the villain in Marc Webb‘s new Untitled Spider-Man Reboot?

According to showbiz411, the actor has made his decision and has chosen the Master of Magnetism.

The First Class cast is now up to three (confirmed) with Fassbender’s recent casting, along with the previously cast Benjamin Walker (Flags of Our Fathers, The War Boys) being cast as Hank McCoy/Beast, and James McAvoy (Wanted) as Professor Charles Xavier.

As far as we know, Amber Heard (Zombieland, Drive Angry 3D) is still reportedly in talks to play the young Raven Darkholme/Mystique, and Rosamund Pike (Surrogates) is still up for the role of either Emma Frost or Charles Xavier’s assistant Moira MacTaggert (depending upon who you ask).

X-Men: First Class is slated to hit theaters on June 3rd, 2011.