Don't forget that the Google ecosystem is not just the "@gmail.com" or "@googlemail.com" domains. There are tons of deployments of Google Apps for Domains, wherein one authenticates using the DNS domain[1] of the hosted system, not via the "traditional" Google credentials.
I could be misunderstanding your concern, however, since the vanilla Apps for Domains does store the credentials in a Google controlled machine, AFAIK. I cannot speak to whether there are any customizable authentication options available with Apps for Domains.
1 = and thus creates a new namespace for usernames
I could be misunderstanding your concern, however, since the vanilla Apps for Domains does store the credentials in a Google controlled machine, AFAIK. I cannot speak to whether there are any customizable authentication options available with Apps for Domains.
1 = and thus creates a new namespace for usernames