Also, take the Java platform for example: it's good old (okay, not old) Java EE 6. Just take your app and deploy it wherever you want (JBoss, Glassfish, Websphere, etc). On AppEngine, you have a blacklisted Java API, proprietary API for common tasks like threads, etc.
I'm still paying for the mistake of deploying on the App Engine. BTW, I spoke with open shift folks and they are going to provide a way to migrate your app to openshift
No, this is not Google AppEngine. The platform is opensourced. You can host this "cloud" on your own servers or rely on some 3rd party provider.