This hook has been deprecated. BuddyPress 2.5.0 Use the filters in BP_Email. $meta argument unset and deprecated instead.
Filters the email that the notification is going to upon successful registration without blog.
(array) User email the notification is being sent to (again). Array key is email address, value is the name.
(string) The user's login name.
(string) The activation key created in wpmu_signup_blog().
(array) Removed in 2.5; now an empty array.