I have just completed the upgrade of my map application to use version 2 of the Google Maps API. I had a few issues but there doesn’t appear to be any problems now. Permalinks generated previously should still work. Unlike Windows Vista I decided to maintain backwards compatibility!
In the new API Google provide a method to automatically calculate the distance between two points. I wrote code to do this in the previous version, which I have now removed, so if you are using a permalink generated using version 1.0 there may be a slight difference between the total distance calculated for the route.
Any problems, please leave a comment.