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NASA Images of Cyclone Nargis
These are images from NASA of Burma, taken before and after the cyclone, showing the effect of massive flooding on the peninsula. Very different from what's shown on the google map.
The point is that we have no real way to deal with this kind of change in online mapping today. Google and Yahoo don't tell you when the underlying images were taken, and in fact the basemaps are often taken from different sources, at different times (see this post on Trulia Hindsight for a vivid example). So in order to do this kind of analysis we have to wait for NASA to release side-by-side maps of areas it thinks we're interested in.
And all the while the world is changing rapidly around us.