Reportedly, the entire cast has been let go, but as of now, the only name anyone is really talking about is Megan Gale, who was set to play Wonder Woman. An agent for Gale (and League costar Teresa Palmer) insist that both actresses are still on board and waiting for the start date to be announced. Industry insiders are claiming the film is off the books for good.
As there hasn't been one scrap of positive or definitive news on this movie in some time, I think it is safe to say the film is dead for the time being. I imagine it will resurrect in a year or two, probably with an entirely new cast and director, but I sincerely doubt George Miller's film will see the light of day. I feel bad for the guy, but it is obviously just not meant to be. He didn't respond to the Herald's inquiries, which may say volumes about whether he thinks the project is alive or not.
I think most Justice League fans will be sighing in relief if the film has met a merciful and early death. And if the film is still going, and it is only Gale who has left, it will be delayed that much further as they search for a replacement.
All I keep thinking is that Wonder Woman just can't catch a break. Who's the first name to flee the sinking ship? Wonder Woman! Then again, that might be in her favor -- and if Justice League: Mortal is dead, perhaps that will see her solo film rise that much sooner.