Apple has released an update for GarageBand and iMovie. Just fixes in both applications. Fire up software update to get the updates.

GarageBand:
* Fixes an issue related to undoing Flex Time edits
* Removes occasional latency that can occur on guitar tracks
* Restores ability to use the Quantize Note Timing menu for tracks with Groove Matching

iMovie:
* Fixes an issue where stabilization would not be applied correctly to some video clips from iPhone and iPod touch.
* Fixes an issue that prevented use of some valid Facebook passwords that contained non-alphanumeric characters.
* Improves compatibility with some cameras that create content in multiple formats.
* Improves performance when scrolling the Project Library.