Apple has releasedAperture, now version 3.1, as well as a handful of helpful troubleshooting knowledge base articles and information documents.
As with any update, it is recommended to create a stable backup of all your important data should anything unexpected go wrong with the installation of the new software.
Several knowledge base articles are available should any of these issues present themselves during installation of the Aperture 3.1 update:
Aperture 3.1 quits when opening after migration
If you have just migrated your data from a Mac running Mac OS X 10.5.8 to a Mac running Mac OS X 10.6.4, Aperture may quit unexpectedly. If this happens, reinstall the Aperture 3.1 update on the machine running Mac OS X 10.6.4.
Not all Aperture 3.1 slideshow themes are available unless iLife '11 is installed
The themes Origami, Reflections, Vintage Prints, Photo Mobile, Holiday Mobile, and Places are only available when iLife '11 is installed. Users can purchase the iLife '11 upgrade here.
These slideshow themes are also only available on Macs running Mac OS X 10.6.x (and iLife '11). Some iLife Media Browser features are also only available on Snow Leopard, including the Faces and Places containers, and flexible sort versions in the iLife Media Browser.
Aperture 3.1 Smart Albums using location data change slightly
This is a feature upgrade in Aperture 3.1, using an improved Places database, making location data more accurate. This could, however, clip some photos from the albums.
Aperture 3.1 Library importing alert
Libraries must be upgraded to version 3.1 before they can be merged into Aperture 3.1. Follow these instructions to accurately import older libraries into Aperture 3.1.