This week I came across PhotoSynth by Microsoft, which aggregates photos to create a seamless whole picture. This is still in beta, but it gives a good picture of how this is going to get continue to become more useful. Right now the demos are using photos taken by one individual or a small team (gotta make the demo look good). But the longer vision of this is to enable users to stitch together their photos based on tags. Or better yet, use the Flickr tags of numerous people to build these 3D views.
From where I sit, this looks like more of the world getting flat. Last summer, when AOL released data on all their searches, it was disturbing to see how quickly the little one or two word phrases that we typed in can be aggregated to give a snapshot of our whole identity. That's the dark side. Finding a way to aggregate those little bits of data and create a larger common consciousness is much more powerful and exciting. We do that intentionally at Wikipedia and now we might begin to see it happen more automatically.

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