This has actually been done many years ago. http://django-nonrel.org . Don't know how it differs from this one, but it has many of the same features. Used it for a project 4 years ago.
Yeah, we used Django-nonrel and Djangoappengine for a long time, and Djangae is heavily inspired by it. However the advantage that Djangae has is that it works with normal Django - it doesn't require a patched fork like djangoappengine.
As for performance, it depends what you are doing. Obviously the datastore is non-relational so it scales much better with a lot of data, and you don't have to deal with things like migrations or connection limits. But then you can't do complex queries and aggregates etc. the good thing about using Djangae is you can make use of Django's multiple database connections to store your data in whichever form makes sense (datastore or CloudSQL).
Yea.. With Managed VMs You can run any VM on the App Engine stack which is f'ing cool. The most obvious use for this is Node IMO, since ppl have gone crazy for that shit. Soon the world will no longer need backend developers or dev ops.
It seems that Mr. Kurzweil has become very influential at Google. This is indeed the future that he predicts, and i can understand why google want's to be a part of that !
The map is highly inaccurate, I guess the designer used Illustrator (or similar vector tool) and applied some effects/transformations to the curves representing the borders.
How is performance compared to using cloud sql ?