I recently migrated my entire Mac System from a 2009 24″ iMac to a new 2010 27″ iMac (Core 2 Duo), and I cannot open Aperture 3 (it crashes unexpectedly). And I noticed that the system is running 10.6.2 and not 10.6.4, which the 2009 iMac was running. So, did something go wrong during the migration process and how can I fix it?
— Tim
You should definitely run software update and get up to 10.6.4. That might fix it. The next thing to try would be to simply re-install Aperture.
In addition to what Gary said, note that Apple have released updates to the Professional Apps series, which includes Aperture. It's entirely possible this includes code that reads/writes the Aperture database.
Make sure your new system has run all software updates. I'd try removing (or just moving) the Aperture library, then run Aperture to check everything's ok. Then either copy the library over from the old system, or use Aperture's import library feature and bring it in that way.