The update iMovie 8.0.4 is available through the usual channels and comes in at 35,2 MB:
This update improves overall stability and fixes a number of other minor issues. The issues addressed include:
Fixed a problem with incorrect rotation when working with video created by iPhone 3GS
Resolved instability when adding multiple beat markers in some languages
Corrected an issue where iMovie could become unresponsive after using fine-tuning controls beyond the stabilized portions of a clip
The update is recommended for all users of iMovie ’09.