Unlike Abra's main newsletter, the new release announcement newsletter is exactly what it claims to be: Abra will use it to inform and link you to new releases, nothing more.
Some of us just aren't interested in newsletters. That's okay! If all you want to do is find out when Abra releases a new book, you can sign up for this newsletter safe in the knowledge that Abra will never, ever use it to send you anything other than new release announcements.