mail list management

[llegrand]

Here's what I need to accomplish:   
Let's say list A is ALL customers (ones who signed up themselves)
List B and C are further refinements I have added to various List A customers for specific marketing purposes.
               list B is customers designated for Monday
               list C is customers designated for Tuesday

I want to send newsletter to only List C customers today,   tomorrow list B,  sometimes List A.

Is there a way within the existing 1.1.7 product to further separate the customers list?  Is it possible to make a subcategory within the customer groups?   or perhaps to add a customer to two categories?   If I add extension for customer attributes will that help accomplish what I want?

Or do I just add all those customer groups as I wish upon approval,  and then choose ALL the groups when I want to send to LIST A  -a bit of a sledgehammer approach.

[abantecart]

Try mailchimp 

[llegrand]

Didn't think about that as a solution.  Will check it out.  Thank you.