It should be possible to bulk mail filtered lists of contacts.

The RedHen Contact module has Views bulk operations integration.

Relevant tutorial: http://thinkshout.com/blog/2012/07/tauno/redhen-and-mandrill-10-minute-s....

We don't yet have in Debut any mail handling like e.g. SMTP or equivalent. That would be good to have, but may not be a prerequisite to an initial solution here.