http://www.macrumors.com/2008/06/10/apple-updates-imovie-7-1-2-and-idvd-7-0-2/
Shortly after the Quicktime 7.5 upgrade, Apple has also released updates for iMovie (7.1.2) and iDVD (7.0.2). Both updates require Quicktime 7.5 to be installed first.
The updates are both described to address general compatibility issues, improve overall stability, and address a number of other minor issues.