An update was released tonight for XCOM: Enemy Unknown.
Changelog for October 11, 2012 update for XCOM: Enemy Unknown Various visibility/hiding optimizations
Multiplayer text chat support (J to activate)
Mouse 4/5 will switch soldiers in the Barracks
ESC hides the movement grid if you do not want to commit to a move while it is activated
Squad Sight ability optimization
Fixed issue when equipping two grenades with Deep Pockets.
Fixed Rapid Fire sometimes consuming too much ammo.
SHIVs that are damaged will no longer become unusable.
Fixed some hangs/soft crashes in tactical combat.
Replaced software cursor with the operating system cursor to reduce lag and framerate dependence.
Fixed rendering bug which causes some soldiers hair to appear as if it is rendering on top of environment fog.
1080p movies are now used at all times on the PC.