The official Counter-Strike blog has been updated with a little banner proclaiming that the game will be simultaneously released on Steam, XBox Live Arcade and Playstation Network on the 21st of August. Preorders should be available from the Steam store page sometime later today and from the PSN store from the 14th.
The game brings modern features to the classic Counter-Strike gameplay including ranked matchmaking to bring together players of equal skill-levels, casual and competitive modes and the new Arms Race mode. Please note that cross-platform play has been dropped as a feature. If you buy the Steam version you will not be able to play with your friends on PSN.Pre-order the game from the Steam store page as soon as it become available!