While rumors of a sequel to last year’s Tron: Legacy have permeated ever since that film’s release, it looks like Disney may finally be moving forward with a follow-up. Though Tron: Legacy did over $400 million, it was a very expensive flick (with a very expensive marketing campaign) and that amount wasn’t exactly the home run the Mouse House was looking for, so they’ve taken their time in deciding whether to move forward or not. Well now, Heat Vision reports that David DiGilio (Eight Below) has been tapped to start writing a sequel to Legacy. That film’s writers, Adam Horowitz and Edward Kitsis, were expected to return if a follow-up came to fruition, but apparently they've been sidetracked by their ABC fairy tale series debuting on ABC this fall, Once Upon a Time.Tron: Legacy set up a possible villain for a sequel with its cameo appearance by Cillian Murphy as the son of corrupt ENCOM CEO Ed Dillinger, played by David Warner in the original Tron. Furthermore, the DVD of Legacy included an epilogue-ish clip of Dillinger conspiring with his father, hinting at even more evilness to come! Hit the jump for more.It’s promising that Disney has hired a writer for a follow-up, but a Legacy sequel is far from a sure-thing. It’s unclear whether director Joseph Kosinski will return (he’s a bit busy at the moment), and the report suggests that the decision to move forward on a sequel may ultimately rest with the success of the animated series Tron: Uprising on Disney XD. This make sense, given that Legacy underperformed at the box-office, Disney wants to make sure that the brand is still relevant, and most importantly that kids will buy lots and lots of toys.While I thought that Legacy looked fantastic, the story and script were a bit lacking. Maybe some fresh blood will be able to punch up a sequel.