Greetings and Salutations :-)
As some of you may already know, the existing "Greeting Type" feature in CiviCRM is pretty broken. You can't use it to specify a greeting for either email or printed / postal communications (no token or export support). In addition, as described in Tony Guzman's recent blog on Better Household Management - it's not designed to support a number of key use cases.
So... Tony and the folks at Dharmatech have been working with us to figure out a flexible WORKING solution which can handle the simple cases ("Dear Dave") as well as the more complex cases ("Dear Dave and Bob", "The Honorable Scout Conberg", etc.). If you haven't read Tony's blog yet - start with the Greetings and Salutations section there. Then, if this is an issue that affects you - check out the details of the proposed implementation in the issue tracker.