First off, Google images are copyrighted. If you want to access them for commercial purposes you need to get Google Earth Pro and it is not cheap.
I love it how the tutorial keeps using Bring to Front. Why is he placing the image he wants on the top on the bottom and then bringing it to the front. Why not just bring them in the way you want them? I don't even understand why he is grouping things, if he used a camera instead he would not need to group anything. Plus I would add a Wiggle behavior at the start or end to get a little shake. I would feather the edges of the images to blend them in better.
For moves that are super long you want to use the Exponential or Logarithmic instead of Ease In. That will even out the Ease in so it doesn't feel like you are going super slow at the end of the move.
He said this is a copy cat tutorial. This is the original and much better:
http://www.videocopilot.net/tutorials/earth_zoom/ Unfortunately for you it is an After Effects Tutorial. Fortunately for you the same concept applies to Motion other then the clouds, but the tutorial you posted covers that well.
Best of luck.
Stephen Smith
Utah Video Productions
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