Treyarch’s design director David Vonderhaar is already hinting that more Call of Duty: Black Ops downloadable content will be on the way. The latest Black Ops DLC, Annihilation was released on the Xbox Live marketplace today costing about £10. PS3 and PC owners will have to wait until a later date. Annihilation features four new competitive multiplayer maps - Hangar 18, Drive-In, Silo and Hazard – and also features a new…