So, finally, I've drawn together my thoughts about keywording in Aperture. My problem with keywording has always been more about "how can I make it easy enough that I will actually do it?", rather than "what should the keywords be?". I'll explain my personal taste for both, though.

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In Aperture, you have not only a hierarchical keyword structure, but also a list of arbitrary key-value pairs for every single image you shoot. This is insane power currently, I believe, hampered by what is a fairly weak interface to that power.

Anyway, again, I was looking for a way to lower the barrier to actually doing the keywording and I found it. The feature has existed in Aperture since 1.0 but the way it’s presented in the documentation really led me away from considering using it on a regular basis.