Yes, you can change the e-mail on your account. To do so you will log in using the e-mail you originally signed up with and clicking "My Account" in the upper right hand corner. From there you can replace the e-mail with the new e-mail. Please note if the e-mail is already in use you won't be able to switch.
You will have to sign up for the promotional e-mails with your new e-mail address!
If you have any trouble, please contact customer service at firstname.lastname@example.org and we can assist you manually if needed.