Here is the huge changelog brought by the latest patch 1.05 for Arma 2.
* Free bonus campaign Eagle Wing
* Free bonus helicopter addon AH-64D
* New Warfare multiplayer mode When Diplomacy Fails, including 3-sides and support for diplomacy between factions
* Major AI tweaking and balancing (better combat cooperation, better situational awareness, new Suppressive fire command)
* Significant performance improvements, especially in large towns
* Fixed compatibility prob
This patch is complete (1.00--> 1.05)