Aperture has seen a few recent updates, and Apple is steadily addressing fixes with the latest major release (version 3.0) with the 3.0.2 update that fixes numerous issues including problems with importing and upgrading libraries from iPhoto and previous versions of Aperture. In addition, a small patch to iMovie '09 (version 8.0.6) has been released to address problems when working with videos from Aperture.
The updates are available via Software Update, but also from Apple's download pages here:
iMovie 8.0.6 (35.84MB)
Aperture 3.0.2 (69.83MB)
For extended information on the Aperture update, see the following Apple knowledgebase document: http://support.apple.com/kb/TS2518
If you have any problems with these updates, please let us know. So far there has not been any suggestion of problems with these updates, but be sure to have a proper backup of your photo libraries and other data before updating.