Yep! Spammers would go crazy in posting large numbers of mails, once this gateway is opened up.

As feature requests, you may like to check out the following:
(*) If you had checked YahooGroups, you can have moderated and then remove moderation for known members.
(*) A unique link (replyto) to authenticate and confirm that the message was sent by a human user and from a valid mailbox instead of posting back.

Vasudevan Deepak Kumar
Personal Web: http://www.lavanyadeepak.tk/
I Blog At: http://deepak.blogdrive.com/