WPMU DEV Automessage is a WordPress Plugin being developed by WPMU. WPMU DEV Automessage allows you to schedule custom welcome emails so you can roll out the red carpet for new users and engage with them from day one.
WPMU DEV Automessage Features :
Trigger campaign when new user is created
Send up to 31 days worth of emails
Multisite and BuddyPress integration
Rocket Genius Gravity Forms Campaign Monitor Addon