[AtlasBarfed]

How about doing customer service with it?

Google: nah.

Honestly I shouldn't even suggest that, it will probably get google groups closed in a whim.

[jmole]

You want something like a ticket/bug tracking system for customer support, not an email group

[ptman]

https://support.google.com/a/users/answer/167430?hl=en

[intrasight]

Google Groups is what I (non-Googler) used for support so I don't understand your comment.