If one could create topics for emails and track the users that open the emails, then one would be able to organically segment their lists. This could lead to better targeting of information without the extra friction of asking people about their preferences.
Thanks for the suggestion. Perhaps you can elaborate a bit more on how the topics idea would work?
This would go along with my other suggestion of tracking the subscribers participation.
By creating topics for emails, and allow a email to cover many topics, you have a mechanism for learning great demographic information about your list.
The choice of the subscriber to join is a message fairly loud and clear they are interested in whatever you say your newsletter is about. However tastes are not segmented so cleanly. Within a list of 5000 people, some of them will be interested in your services, some interested in your products. Or, some might emotional, others methodical about their choices.
By dropping a series of email with different segments attached to the actions, you organically allow people to segment themselves. This is a frictionless method of testing your list versus asking them to join another or different list. Joining another list is a all or nothing event where as participation in a segment allow a person to be more.
It is up to the newsletter designer to understand the tool, of course, in order to get pertinent information. Empowered with this, as a marketer, I'm sure I could target copy and offers at the right people and get more value for my dollar. I believe this would make your service much more "affordable" since the ROI would increase over time.
I think that's a great idea - it adds another dimension to the targeting process, in a way.
BTW: Congrats on the release of the testing feature - that's a big one. What's do you think will be the next feature to be added?