I'm actually looking forward to seeing how they portray Batman now -- if he is the antagonist in the film then we really have the potential of seeing Batman infiltrating this world of MoS -- he creates the Kryptonite, the only weapon against the Kryptonians -- and this immediately places his role in the continuity as one of the most intelligent and formidable forces to deal with. To draw parallels with the DKR it'd mean that the govt would really have someone to fear in this masked crusader who has bested even the Man of Steel. We see lingering nods to John Byrne's MoS issue where Bats & Supes meet up, their initial antagonisms, their mutual alliance, and ulitmately their inevitable encounter at Crime Alley where the kryptonite is exposed the most and Clark is faced with an even greater threat than before because not only is he careful on not killing anyone this time, not only is he alone facing certain death, but he's actually getting beaten by a mere human being.
Thematically, Kryptonite could be the next big addition to the Superman cinematic franchise by putting in the Dark Knight's fingers...