One interesting feature to the App Engine which you may not have noticed, is the integration with Google Apps. Not only can you tie an application to your domain (allowing you to have myapp.mydomain.com instead of myapp.appspot.com) but you can restrict access to the given application to only members of your domain. If I ran a company on Google Apps, this would be a nice addition. I could see the small business apps that I need running there.

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