"Variety" is reporting that David S. Goyer is in early talks to create the story for the sequel. Cage will presumably be back for more given how excited he's sounded about it.
No word on whether the director of the first film, Mark Steven Johnson, will be back as well. In the "Variety" piece, former Marvel head Avi Arad, who will produce "Ghost Rider 2," also talked up some of the other Marvel properties that might find their way to the screen given the Disney acquisition-- Dr. Strange, Nick Fury, Power Pack, Guardians of the Galaxy, and The Avengers all got name checked, even though Fury and the Avengers are already part of ongoing movies. I guess he just want to remind everyone at every turn of just how many Marvel characters we're dealing.
As for the Ghost Rider movie, the sequel seems to mostly be motivated from Sony's desire to keep the property and not cede it do Disney. They can't keep the movie in development forever without progress, of course. I wouldn't expect to see this one actually coming to fruition any time soon.