Just noticed this on eBay. Ps4 version has dropped today from £27.99 to £19.99. 'Brand new sealed'. Only released 23rd August! Got into this series recently via Human Revolution, so I've been looking for this.
Xbox One version still £27.99.
13 already bought today at the new price.
This is the Day 1 Edition which includes the following bonus DLC;
Three Weapon/Item Packs
Extra In-Game Mission
Digital OST Sampler, Digital Comic Book, Digital Novella & Digital Artbook