When Google launched its AppEngine utility computing platform last week, one of the early criticisms was that the structure of AppEngine would make it difficult to build an application on Google and then move it to another service. Yesterday Tim O'Reilly addressed this concern in a post titled Is Google AppEngine A Lock-In Play?
The question was answered in the comments, as developer Chris Anderson posted a link to AppDrop, a service that allows users to deploy applications created in AppEngine on Amazon's EC2 platform.
Here's more from Andy Baio at Waxy.org:
AppDrop is a container for applications developed with the Google App Engine SDK, running entirely on Amazon's EC2 infrastructure. Just like Google's Appspot, anyone can use a modified SDK to deploy their App Engine apps directly to Amazon EC2 instead of Google, and they work without modification. This proof-of-concept was built in only four days and can be deployed in virtually any Linux/Unix hosting environment, showing that moving applications off Google's servers isn't as hard as everyone thought.
Vendor lock-in will be an issue as more cloud computing platforms emerge. In demonstrating portability between two major platforms, AppDrop's proof-of-concept introduces apps that can jump from cloud to cloud.
UPDATE: James Urquhart has offered additional analysis on How AppDrop Does and Does Not Affect Lock-In.