Link: http://googlesystem.blogspot.com/2009/09/google-earth-51-loads-faster.html

Which is a good thing , (we're talking the desktop client here) - Loading the thing especially on an older laptop is dog slow, so the Google Earth team worked on that...

We've made a lot of adjustments under the hood, like improving memory utilization so we can show more buildings, layers, and user content. We improved our shaders (that's graphics-speak for small programs that run inside your graphics processor) to make the atmosphere draw faster. We also worked to reduce stuttering (known as frame drops) to provide an even smoother experience as you fly around the globe. When we draw imagery, we now use compression technology to use less memory and graphics resources.

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