Understanding Autosubscribe

Here is my use-case:

Private online-collaboration work-space for about 12 people. I want the default to be that each user is subscribed to everything on the site. I've imported my users (with no notification). On my very first e-mail to them, via a posting to the web site, I want them to receive notification of that posting and everything else on the site unless they unsubscribe.

I thought the auto-subscribing feature was for this use-case but it didn't seem to work. After I turned it on and then logged in as a different user and went to "My account" the user wasn't subscribed to anything. I didn't actually add anything to the site at that point because the user-emails are real and I don't want them to receive testing content.

Thanks for your help.

[p.s. - this module/framework is awesome. The api approach you're taking makes it powerful and flexible. As with other API-oriented drupal solutions, documentation is both really critical AND harder to do. I'd like to volunteer with helping out on documentation after I understand the framework a little better; I'll make a screencast or do something else to help along these lines.]

Shai