Excellent to know that the member limit was lifted. I hope the Followers information in the documentation will be updated so others aren't confused at this change in user permissions.
The site is not private though we wanted it to be. We've left it open to the public for months but not indexed by search engines because of all the Theme and user invite issues. I wanted to make sure that the right folks could look at it and help us figure out the bugs in P2, login issues, and user permissions.
We've waited several days between invitations and acceptance and they still do not show up in the user list. We've done all variations from new users to current users. It happens the most consistently with new user invites, but also happens with current users, just less frequently. If it was consistent, this would be so much easier.
Let's see if I can break it down.
We've sent invites to people not registered with WordPress.com which included an invite to join. They joined, they don't show up on the user list, just in the invite list as "waiting." We've confirmed that they've joined and are signed in (they see the admin bar across the top but have no access to the blog.). We send another invite as "author" and they click the invite and they still don't see the blog on their admin bar and it still said "waiting" on the invite list. Time passes. We keep trying, eventually it works, but we now have people frustrated with WordPress and they haven't even used it yet.
We ask people to sign up for WordPress.com and give us their email address that they registered their account with. We send an invite to become an "author" (save for the one boo boo as a follower - we'll fix that). They click the email to confirm. We wait. Nothing. 24 hours nothing. It still says "waiting" on the invite list. We send again. Sometimes nothing, sometimes it works instantly. If not, we try again. It can take 3-4 tries. Rarely does it work immediately.
When we first started the site, one of the issues we had was with user names as two of them were pre-beta logins, thus had whack user id numbers or something. I think that was fixed but that should have nothing to do with those admins sending out invites...grasping at anything. :D