Contrary to what was rumored, Stephen Toblowsky is not slated to appear in Justice League: Mortal as Batman's butler, Alfred Pennyworth. Toblowsky, who appears on NBC's Heroes, spoke to Moviehole about the status of the rumors.
I sent all of the stories to my manager who has zero idea where the stories came from...who contacted Warners...who has no idea where the story came from. The studio said they don't even have a script....that they expect a draft in two MONTHS...they have not secured the super heroes yet let alone their butlers...we shall see.
So, not only is Toblowsky not (currently) slated in the film, but it seems like none of the other expected Justice League: Mortal casting is set in stone either.