I can't supply any relevant answers to the original question, from here in Oz but some of the posters above have reminded me of a couple of things.
When someone on our local intranet discovered GoogleEarth and alerted the rest of us to the URL of our workplace on it I was intrigued about when the aerial photo had been taken. When I posted that question the game of narrowing the time window by using the usual types of photgraphic evidence was great fun. But it only works where the resolution is adequate and there seems to be no understandable rationale behind which areas in Oz have high (or low) resolution images.
With reference to stereo pairs of airphotos, it's a longstanding trick for municipal councils here to use them for identifying "unapproved" alterations to buildings. Instead of putting adjacent pairs from the same run under the stereoscope (as alluded to by Charley Noble), you put the photos from the earlier run under one mirror and the photos from the later run under the other mirror. When you are viewing the same 'location', the items common to both runs are 'seen' in 3D but items 'seen' in only one of the piccies will appear to be 'floating'. Most of them will be vehicles but house extensions and other alterations to buildings will also appear to be floating. A quick check of the database for whether the work was "approved" and Bob's your uncle.