Hmm, I'm not sure we'll get access to the raw data though, but rather a widget with which one can interact. It would be nice to have an api for the renderer (as I have no real desire to write one of those) and low-level access to the meta-data associated with the vector maps.

Take a look at the various Javascript files that come with the Maps app.

You never know, it might not be so bad reverse-engineering the binary that also comes with Maps (I'm assuming this contains the rendering code, etc.)