They'll probably bring in Lex Luthor, but he's kind of the go-to villain in the Superman movies and, personally, I'm getting bored with him.
In some ways though, Luthor is the go-to name for a villain. Other than having the same name, there is little continuinty between various incarnations of Luthor. He is a very different character in Smallville, L&C, the Animated Series, The Christopher Reeve movies, various incarnations in the comics.
Clark and Lois are always reporters, Lex is only consistently the bad guy.
