When does family/friends announcements turn to spam? I know many marketing email providers are weary of writing to your entire address book of people who did not opt in.
We actually looked at using MailChimp for this, but we didn't want to go outside of the TOS. So, we ended up merging the mail locally using Thunderbird and sending it from our personal accounts. I am sure there is more to be said about the line between the two, however.
