New Wordpress 3.x or Wordpress MU

               Hi to all, have you upgraded your Wordpress site to the latest version 3.1 or the they called the Worpress MU. Wordpress MU (Multi User) allow the administrator to setup sub-domain and sub-folder for its site. Furthermore you can add user for every sub-blog/sub-domain/sub-folder that you created.
Wordpress 3.1 has the SUPER ADMIN access that can set all the functionality for its sub-domains and sub-folder. Some of the functionality that SUPER ADMIN can handle is the installation Network installation plugins, different themes for each sub-domain site, and the
hierarchy of user.

Start your Wordpress blog now :http://wordpress.org/download/ or upgrade now.

For more information:http://mu.wordpress.org/forums/

here is the steps on how to activate network in wordpress Mu.