The 2K Games Forums have a list of the changes in a new patch for XCOM: Enemy Unknown that's now available to update the newly released installment in the counter-UFO strategy series (thanks Scott). Here's word on what this does:

We wanted to let you know the details for the PC update for XCOM: Enemy Unknown that went live today (10/11/12). I've included the notes on this patch below:

• Various visibility/hiding optimizations
• Multiplayer text chat support (press J to activate)
• Mouse button 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 soldier’s hair to appear as if it is rendering on top of environment fog.
• 1080p movies are now used at all times on the PC.