Riot Games has announced that WASD movement will go live in League of Legends as part of 25.24 patch on December 3rd.
The new movement system, which has recently been in public beta testing (PBE), aims to provide players with an alternative control scheme to use in matches.
WASD movement will seemingly be slowly introduced, with it going live in the League of Legends client for all queues except for ranked and normal draft games.
Testing of WASD movement in League of Legends began in the Autumn, arriving in the PBE to allow developers to identify and resolve bugs before introducing the control scheme.