Apple Computer updated QuickTime to version 7.0.3, an update that includes both bug fixes and new features. Apple designated the bug fixes as "important," and said they were primarily in the areas of video streaming and H.264 video, without offering details.
The update also gives QuickTime 7 Pro users the ability to "create video and audio files that can be played back on compatible iPods."
The update notes in Software Update also specify that it will disable QuickTime Pro functionality in prior versions of QuickTime (i.e. QuickTime 5 or QuickTime 6).
You can find the update in Software Update in Mac OS X.