Apple today has released Aperture 1.5.2 for Mac, an update to its flagship photo management and RAW conversion application. The notes about the update highlight the following changes:

Aperture 1.5.2 addresses issues related to overall reliability and performance in a number of areas, including: Contact sheet printing Smart Albums Watermarks Lift and stamp Image export Versions created using an external editor

The update is a free download via the Software Update mechanism built into Mac OS X, or as a standalone updater here (Apple ID and Aperture serial number required). More information about v1.5.2 is in the Apple support document Late Breaking News About Aperture.

Aperture trial version also updated

Though the 1.5.2 updater can't be applied to an already-installed trial version of Aperture, the trial version of the application itself has been updated to v1.5.2. Therefore, if you're currently trying-before-buying, you'll need to download and install the trial from scratch again to get Aperture 1.5.2:

If you download the current version of the Aperture Trial, you’ll receive Aperture 1.5.2. If you downloaded the Trial previously, you can download the new version, but the 30-day period of the trial will continue from the date of first usage. Please note that Aperture updates available via Software Update or the Aperture Download page can be used only to update purchased versions of Aperture and cannot be used to update Aperture Trial software.