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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.