WordPress Mu and BuddyPress
The system that WordPress Mu has launched in this line is BuddyPress, which began as an advanced project of WordPress Mu and now is a project that is being developed within WordPress Mu itself, very well, and also has the following features:
Advanced profiles: Which allows you to create advanced profiles in the system.
Personal Blog: Of each user
Private messages: Between members, allowing them to communicate with each other and with other users.
Friends: You can connect them as friends and allow them to connect or not.
Groups: Groups allow users to share posts, photos, and other content.
Status Update: Appears on each user’s page so you can see how each user is doing.
Albums: Allow members and users to upload their photos and allow others to see them or not.
The current version of Buddypress allows the development of quite acceptable systems, those developed until now were somewhat complex to finish the configuration and sometimes gave some failures.