Here is a small Aperture tip I forgot to mention.

I work on Aperture on two machines, my Powerbook G4 and my girlfriend’s PowerMac G5 when I can sneak in some time. One problem I ran into was finding that the keywords (and also various export settings) I have set up in Aperture are not carried with the Aperture Library.

The trick is realizing that they are stored in your home directory in: “~/Library/Application Support/Aperture”

To carry them with you to the other machine, simply copy this folder from the machine you set Aperture up on to the one you haven’t. Then the export presets, keywords, and keyword sets will become available to that machine.