You cannot play as a Vampire in The Sims 3 on Xbox 360.
Missing (PC/Mac only): Late Night, Seasons, Supernatural, University Life, Island Paradise, Into the Future.
For the full occult experience (Vampires, Werewolves, Fairies, Witches, Spellcasting), you **must play on PC or Mac** (The Sims 3 + Supernatural + Late Night). The console version is a distinct, limited product.