Microsoft Live Labs is working on a photo recognition system that will compare photos with each other to create 3D images. This will also allow tagged items on photos to be shared from photo to photo. Imagine, for instance, comparing your photos of Jerusalem to a worldwide database, with the result that your pictures are automatically identified and labeled. Maybe that day is not so far off. In Microsoft’s words:

Photosynth takes a large collection of photos of a place or object, analyzes them for similarities, and displays them in a reconstructed 3-Dimensional space. With Photosynth you can:

• walk or fly through a scene to see photos from any angle;
• seamlessly zoom in or out of a photograph even if it’s gigapixels in size;
• see where pictures were taken in relation to one another;
• find similar photos to the one you’re currently viewing;
• explore a custom tour or see where you’ve been; or
• send a collection to a friend.

Here’s a video about Photosynth.