Well, I'd hardly blame the actors for Hollywood's lack of originality. But you're right--so many of the new movies coming out as of late are based on existing properties or a remake.

Five out of Five of my favorite movies of this year are already available in at least two other formats:

Batman Begins
Serenity (Firefly TV show and comics)
Hitchhiker's Guide (Novels, BBC show, radio drama)
King Kong (based on a little known picture from the first half of the century)
Narnia (BBC Drama, cartoon, Novels)