You can make a registration form with the Forms Module, and they tie the results from these forms with the Newsletters. The newsletters mappings can be bound to any field of the target list.
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items