For those wondering about this transition, here is a link to some good info from MIT.
Here is some of the main info:
When will the Google App Inventor service shut down?
Google support of App Inventor will end on December 31, 2011.
When will the public MIT App Inventor service be available?
We MIT anticipate the public instance of App Inventor will be available for the general public to access some time in the first quarter of 2012.
Will my current App Inventor projects transfer automatically to the MIT service?
No, legally Google is not allowed to give your project data to MIT. You will need to download your projects to your computer and upload them to the MIT service when it becomes available.
What do I need to do to preserve my projects when the Google service shuts down?
You will need to download your projects to your computer. The “Download all projects” button will create a zip file of all your projects. Unzipping that will produce a folder with all your projects (each project itself is a zip file) and you can upload them individually to a new App Inventor service when it becomes available.
Link to the rest:
App Inventor transition to MIT