Microsoft Photosynth is going to revolutionize the way you sort pictures. Right now you sort pictures according to your own tags, labels, or folders. Photosynth synthetizes a 3D environment based on the images in your pictures. Example: if you go to India, take pictures all around the Taj Mahal, Photosynth can arrange your images according to WHERE you took it around the Taj, in a 3D space, presumably merging with data available from the pictures of other people all around the Internet.
And this would add a further dimension to your pictures, much more than GPS geotagging. It will augment reality, give you a much more powerful view, and from a human point of view, evoke more intimate emotions about your pictures.
Check out the video here: