That is up to you, anyone who signs up through your personal Ai links will be emailed on your behalf automatically.
If you want to personally write to your audience and engage with them you will need an auto-responder like Aweber.
At the moment, you can integrate Aweber or GetResponse with your Ai back office by going to the Integrations Tab located in your Account Settings page. Find the Email Integrations section, insert your Aweber/GetResponse List ID into the appropriate box and click the green Save Account Settings button at the bottom of the page.
This will enable all your leads to populate into the list you entered.