Counter-Strike: Global Offensive was developed by Valve and Hidden Path Entertainment. It began as a port of Counter-Strike: Source to the Xbox 360 by Hidden Path Entertainment. Valve saw the opportunity to turn the port into a full game and expand on Counter-Strike's game play. Global Offensive started development in March, 2010 and was revealed on August 12, 2011.
Counter-Strike: Global Offensive otherwise known as CS:GO is the next iteration in the Counter-Strike series. Counter-Strike is a fast paced, competitively played first person shooter game which has a very strong online presence. The game series has been in existence for around 12 years since early 1999 when it started out as a mod for Half-Life. In 2004 the series was updated when Counter-Strike: Source was released which come packaged with Half-Life 2. A massive 25 million copies has been sold world wide and the game still has a strong following.
Counter-Strike: Global Offensive looks to continue this amazing feat, updating the series once more in the latest version of the Source engine (Portal 2 version). The game will feature new weapons, new maps, new game play modes, updated graphics, new characters, match making, leader boards and various tweaks and improvements over the previous CS titles. It will have two different match making modes (competitive and casual). The cross platform play was announced but has since been dropped and instead the game will be released separately on Xbox360, Playstation 3, PC and Mac.
The Counter-Strike: Global Offensive beta concluded on the 21st August 2012. It began on November 30th, 2011. Access to the beta was open to everyone who had pre-ordered the game, this happened on August 14th, 2012. Counter-Strike: Global Offensive is now available on the Steam Store.
Valve had released a survey which you could fill out to increase your chances of gaining a beta key. Otherwise you had to attain one through other means such as third party websites giving out keys through contests and promotions or through receiving an invite from a friend.
The beta had a limited amount of maps for both the standard game mode (casual and competitive) as well as the arsenal game mode. Every so often beta updates were released based on feedback given by the community to tweak and polish the gameplay and eliminate bugs and imbalances. Expect new maps, new guns and new content to arise in the coming weeks and months to the full version of Counter-Strike: Global Offensive.
A list of the CS:GO Beta Updates can be found over at Steam.
A list of the most recent CS:GO Updates can be found over at Steam.
An excellent CS:GO Beta FAQ can be found over at counter-strike.net.