Talk about taking over the world!
Google's plan to host all the Ajax libraries you'll ever need is breathtaking.
So, we developers will all routinely hook in to Google's servers whenever we want to use a particular JS library, and, surprisingly, Google will have a couple more ways to add value : statistics and Analytics will be a tick-box away, sharing Google's id system will be an easy upsell to us. It will pull people towards GAE because if you already trust Google to host your js libraries, why not the rest of your application?
Google can embrace and extend the libraries, offering their own extensions, whether the original devlopers want them or not.
And finally, it will become too much trouble to use this stuff any other way.
Wow! Like I say, breathtaking.
(Hat tip Folknology)