”Children of Men” helmer Alfonso Cuarón‘s 3D sci-fi epic “Gravity” starring George Clooneyand Sandra Bullock just started filming in June, and WB has already scheduled the film for a November 21, 2012 release date. The move is curious considering early versions of the script, dated late 2009, written by Cuarón, his son Jonás and filmmaker Rodrigo Garcia (”Mother and Child”) displayed a fairly straight-forward action-sci-fi picture, albeit utilizing long stretches of silence. However, considering its lengthy gestating period and its new Oscar-centric date, it’s feasible the the screenplay has gone through a significant overhaul, or there is much more riding beneath the surface than we expected (and as one commenter reminds us, it could come off as “127 Hours” in space with an equally riveting third-act climax).