The trouble with coding across the Clouds, part 2
The best cloud applications have development (or at least scripting) capabilities for creating and extending the platform's database and computational capabilities. But even the best of the cloud applications must put in limiters for their platform/development environments: an app isn't a general purpose run-time or generic object container. For example, the development language must be made safe for a multi-tenant deployment, and must be well-behaved so that user code can't take down the virtual machine, database, or overall application.