Major Nelson posted a recent Podcast with an interview with Jason Bergman. He outlined very Key Features

the DLC has a start and end slide show, Veronica will have new speech options and a new perk, Dog is schizophrenic and also is called God, christine is the Bald mute female, Dean is the lounge singing Ghoul. Each have different Perks. They are optional to have at one time, but will interact with them. The DLC is about 4-6 hours. Ghost people need to be decapitate. New Weapons include the Holo-Gun. Bearclaw Fist and many other new weapons.