According to the Microsoft support center release note, this update will resolve the following issues of Windows 7 and Server 2008 R2.
1. “Keyboard function keys or keyboard shortcuts, such as mute or calculator, may not work correctly”.
2. “The notification icon for an application may be moved or lost when the executable application is updated”.
3. “On a computer that is running Windows 7, you configure the Screen Saver Settings to display the logon screen on resume or configure the computer to go to sleep. But, the computer may not go to sleep after the screen saver starts “Instead, a black screen is displayed”.
“This problem causes the operating system to stop responding. You must restart the computer by holding down the power button”.
You can get more information and download the update at Microsoft Support Center.