Little is known about the plot, though the big news is which studio would snatch it up. According to Deadline, the feeling is strong that it will be Sony. Notes the site, "Insiders tell me Sony Pictures won't let this one get away. Expect Amy Pascal to announce shortly that she has filled a tent pole slot in her release schedule. Emmerich deals generally mean a big upfront payment, big gross commitment and also a guarantee the studio will green light the movie per Emmerich's blueprint."
More as info becomes available.