The "digital feature" is slated to have David Zucker on as Executive Producer with Sergio Mimica-Gezzan (Heroes, Battlestar Galactica) on as the Director. According to The Wrap, a "digital feature project" indicates that it's a film that won't have a theatrical release. It will more than likely be digitally released first through the Xbox One and possibly Xbox 360 video services.
Microsoft also notes that this digital feature is "completely separate" from the Halo TV series that Steven Spielberg is going to be Executive Producer on.