I'm one of those people who firmly believe that metadata is important, but only if it is relatively invisible. It needs to be there, but can't get in the way. I've been thinking quite a lot about this lately, especially since we're working on APOLLO (well, ok... it's mostly King working on it, but I still get to think about this stuff ;-)

One application that really demonstrates this principle quite well is iPhoto. I've got 2868 images in my iPhoto library, and each one has several bits of metadata associated with it. Creation date. File size. Dimensions. Resolution. Title. Keywords. Comments. Great stuff, in that none of it is really necessary (except, perhaps for the ones that are tied directly to the original image file).

The cool thing about iPhoto is that it works just fine straight out of the box, with nothing added. I don't have to add any more metadata, or spend any time organizing anything, and I'll still find iPhoto useful.

However, it really starts to sing if I take a small amount of time and massage the metadata (add titles rather than using the filename generated by my camera). The most powerful way to demonstrate the value of metadata is by creating a "Smart Album". This is essentially a saved query that is displayed as a normal photo album.

I just created 2 smart albums (I have others, but I was wanting to see if this was possible). These albums mine through my library, and display images from a specific week. One library displays "This time last year..." - images from this week last year. The query was a little more funky than I would have guessed, and amounts to:

Show images within the last 52 weeks.
Exclude images within the last 51 weeks.

Works great. I can see that last year, my brother Kevin was in Australia on business (or golfing, depending on who you talk to), and Evan was showing off his first bluejeans (holy crap has he changed in 1 year!).

The second Smart Album I created displays this week 2 years ago. Wow. What a difference 2 years makes. Evan was still a bun in the oven, and his cousin Hailey still looked like a baby.

Here's a screenshot of "This time last year..."

This Time Last Year...