In an article detailing the latest actresses mentioned in connection with the female lead in Superman, Cinematical offer the following..
Meanwhile, the hunt is also on for the film's villain. No word on whether we'll see yet another Lex Luthor storyline, though we would expect some bigger things, like maybe the inclusion of Doomsday (which is a character we've heard some whispering about). With production set to begin this summer, expect a lot more Man of Steel news to hit in the coming weeks.
I know, it's not too much to go on, but whispers are better than silence and we haven't heard a peep on any potential villains in quite a while. Plus it's not too much of a stretch to think that a visual and action orientated director like Snyder might want to give Superman a chance at a throw down, knock out brawl in his movie. We still don't know if Lex Luthor will be involved, General Zod appeared to be debunked by Snyder himself. And Brainiac, although a very popular choice among fans has never been brought up except in fan fic. The only reason Doomsday seems like a strange choice is that aside from offering the prospect of a great scrap on-screen he doesn't really bring much else to the table. Could he be only one villain with another more cerebral one in the mix too?
Anyway, like I said there is nothing solid here. I'm going to see if I can dig up any more info. But IF Doomsday were to be a p[art of the movie, how would you feel about it?