Subscription ID: If you created your account prior to October 11, 2005,
you have a Subscription ID. If you have already built
an Amazon Web Services application using your Subscription ID,
you may continue using your Subscription ID.
If you are building a new application, we encourage you to use your Secret Access Key and Access Key ID instead.

うわ、、10/11で配るの辞めたっぽい。。