Just a heads up, tickets can be bought at expo.eurogamer.net lots of playable games (including KZ2, Gears 2, Resi5, Resistance 2, Motorstorm, Dead Space, Left 4 Deadm etc) £5 a ticket open next Tues and Weds at some venue near Brick Lane.
I've got my ticket (along with some friends) for the Tues, hoping to see some fellow VGCers there.