There is no norm, but if you want to put the name of the group in the To:
field, this MS KB article may help:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q266339

Signature
Russ Valentine
[MVP-Outlook]
>I wish to send an e mail publication to a group of contacts
>
[quoted text clipped - 7 lines]
> the Person In the Send to box.
> regards