Hi,

one great feature would be if you could import receipients from other app via webservices or something like that (like MS CRM or whatever, as umbraco wouldn't be my first choice to store semi-sensitive user data as email addresses and some customized MS CRM instances i've seen have some nice logic to identify and track non-reachable receipients), so one could create the newsletter content within umbraco, but the subscription management itself is handled by some other app.

Just my 2 cents,
André