Apple released an update for Aperture yesterday which offers many bug fixes. To be as accurate as possible, I’ll just quote Apple:
Aperture 1.5.1 addresses more than 100 issues related to overall reliability and performance in all areas of the application. Here is a partial summary of the specific issues that have been addressed in this release.
Wow, over 100 issues. With the release of a trial version of Aperture yesterday, and now news of this update, it is clear the the Aperture team has been hard at work—just like that little truck above.