Been waiting for a good pre-order for this game (seeing as I can't get the GameSpot one without paying outrageous shipping costs!). You get a free exclusive Darksiders T-shirt which is being sold for £15.99. Personally I think this is a better offer than the bonus codes from Play or Amazon as these will probably be unlocked within the game eventually or download/puchase via psn. Cheapest online pre-order price currently too.
"Penned by legendary comic book artist Joe Madureira (X-Men, Battle Chasers, The Ultimates), Darksiders: Wrath of War is set in a Post-Apocalyptic demon-ravaged world where evil forces have prematurely brought about the end of the time. Originally sent to oversee the destruction of Earth, the Four Horsemen of the Apocalypse have been betrayed by their master, stripped of their powers and cast down to Earth. Players take on the role of WAR, the first of the Four Horsemen as he embarks on a brutal quest of vengeance and revenge against the forces that betrayed him with the help of his phantom steed RUIN. Darksiders: Wrath of War features open-world exploration, a deep combat system and a huge arsenal of modern and mythical weapons."
Quidco is 4% but not sure if pre-orders apply. Also, dont forget the £1 voucher floating about if you haven't already used it!