[ww520]

I haven't looked at AppEngine lately but I believe you cannot run Rails on it. It has its own proprietary service and API that you have to write against. It's not like EC2 where you pretty much can install anything and do whatever.

[ldargin]

You should be able to run Rails apps on AppEngine through JRuby.

[ww520]

Is there an ActiveRecord binding to AppEngine Datastore?

[ldargin]

I don't think so, but you should be able to use a "Google Cloud SQL" db, which is MySQL.