Hertz has a nice campaign running encouraging those that are a Hertz #1 Club Gold member to complete their account information and include their email address; effectively providing an opt-in.

A few interesting messages in the message:

• They provide a link to a 'sample' message
• They promise to only send this message once: "As we respect your privacy, we want to assure you that we won't send any future e-mails on this topic."

What are your thoughts on this approach? Are you sending 1-time opt-in messages to your account members that are not currently subscribed?

A view of the creative: