Uninstalling an App that uses the Accounts tab

Hello,

We are in the process of testing an app for the AppExchange. Our app includes the Accounts tab from Salesforce.com. When we try to Uninstall the app, there is a big warning about *all* associated data being immediately destroyed. Does this apply to standard Salesforce.com data? It won't really delete all the Accounts will it?

Thanks,
--Sarah