This is my attempt to document some of the changes made by Google maps in their update from .3 to w2.4.

You can see two large updates in these images. Fist, the projection is more realistic now, and second, the road lines have been made darker. The satellite images are still using the old projection, though. Update 2005-07-23: As of yesterday (and perhaps earlier) the satellite maps have the new projection as well.

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They've also added one way direction arrows to roads that need them. This is very handy in Seattle. Also, as you can see in these images, they have started adding building outlines of major landmarks.

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They've changed the URL slightly between the new and old versions, and have made the tiles bigger. I assume people have larger screens then they expected, so having larger images will reduce the number of images needed to ownload and may make it run faster because the javascript doesn't have to keep track of as many things. Along with the URL and size changes, the tile numberes have also changed.

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Old URL: http://mt.google.com/mt?v=.3&x=-5&y=-3&zoom=13
New URL: http://mt.google.com/mt?v=w2.4&x=1&y=4&zoom=13

If you like, you can also view the difference between old downtown Seattle and new downtown Seattle.

You can now zoom out a lot farther.

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Allowing you to view more of the world at once (before the rest of the world wasn't there; it was only the USA and UK). Both of these are at the farthest position.

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Update 2005-07-23: At some point they updated the map version number again. Now it is up to 2.5. http://mt.google.com/mt?v=w2.5&x=1&y=4&zoom=13

Update 2006-01-05: Google is now up to version 2.7. For a few months I've been noticing image version ap.3 on some Google maps mashups (only some), but never on the original site. This version features more building outlines. Also, today I noticed that you seem to be able to reach a higher resolution level for satellite maps, but none of the places I viewed had the higher resolution files. Here are the differences between w2.7 and ap.3:
w2.7 ap.3
Or, try comparing these two:
http://mt3.google.com/mt?n=404&v=w2.7&x=5251&y=11444&zoom=2
http://mt3.google.com/mt?n=404&v=ap.3&x=5251&y=11444&zoom=2