I couldn't be more thrilled with her new villainous origin. She needs this so she can eventually have her redemption. Donna's been my favorite DC character since I was a child and I think I'll enjoy her being sort of a dark reflection of Diana similar to the relationship shared by Buffy and Faith (which is awesome). I do hope they eventually find that sisterly bond. If not, I'll settle for great friends and allies.
Glad to have my girl back and hopefully she'll give everyone some good villainous beatdowns (lol). If my girl's gonna be a villain right now, she better be one of the best at it;-)