My Windows 7 PC just picked up this update via Windows Updates. KB963660
"In prerelease versions of Windows 7, certain audio and video     codecs       expire after 90 days.     When you try to perform certain operations in this situation, such as DVD     playback, TV playback, and some device sync operations, the operation  fails     with an error message such as "Decoder not found." The affected codecs include     MPGG-2,     H.264, and AAC. Additionally,     Dolby Digital-related media may     not          play successfully.     In this situation,     you also receive the  "Decoder not found" error message.
This     problem occurs because the trial period of the components  expires on March     15, 2009. After you apply this update, certain audio and video codecs will not     expire on this date."
UPDATE:
Is anyone else having problems installing this update? On my machine it says failure configuring updates, then, reverting changes.
I have FFDShow Tryouts Beta 6 and Haali Media Splitter installed.