Mass Mailer & Primary Blog plugin problem

Hello everyone,

When I installed the Primary Blog plugin to allow users to select their primary blog, the ability for users to opt-in or out of receiving admin e-mails vanished. As a result (or what I believe is a result), only 51 of 701 users are able to receive admin e-mails, suggesting that when I added the Primary Blog plugin all users who signed up afterwards were somehow automatically opted-out, does this make any sense? I'm not certain their is a direct cause and effect here, but it is the assumption I am running on.

Anyone have something similar happen to them?

Anyone know of another to automatically sign users up for admin e-mails? If not, might there be another way to contact all 700 users easily?