Does enewsletter need subscriptions plugin to auto subscribe new users as members for mailing?

So i notice (which is good) that new users who signed up for the main blog WPMU/BP are being added to the blog.

Does the newsletter plugin pull all new members or I was wondering if the "subscription" plugin is doing this for the enewsletter.

Basically, i want to turn off the subscription plugin. If I do so, I want the enewsletter to continue to add new letters as mailing members so i have the option to email to them.