Yes, there are a few ways in which this can work.
Option #1 – CSS
If the email input field has a CSS class of .validate-email on it, then MageMail should pick up any changes made to that field and save them for the abandoned cart.
Option #2 – Custom Javascript
If that doesn’t work, another option is using custom javascript. You can use:
MageMail_Magento.captureEmail(emailValue)from within your custom javascript. That will capture the email address for the purposes of the abandoned cart email.
