It is very simple. I will explain to you how to do it. Use 1 WordPress MU site for the database and then integrate each bbpress with cookies and user database integration. It works fine. I’ve done it!
I thought the plan wasn’t to give it away? Such as with the buddpress.org?
@ipstenu: I know iframes are dangerous but it was the simplest way of getting the job done.
@everyone: thanks for your support!
I agree with iframes being evil.
I guess, but you would assume he would have copied and pasted that in if he followed the plugins directons.
(not recommended) Remove the bbpress header.php and replace it with a symlink to the wordpress header.php
(recommended) Deep Integrate WordPress and bbPress and have bbpress call the wordpress header not the bbpress header.
There is an administration panel, in there there is settings. Go to General Setting and set the bbPress address (URL) to the domain you want it to appear on.
He also said:
I have already installed the plugin bbPress Integration for WordPress.
which implies that he already added the code, 
They won’t be giving away the theme. It was custom made for this site.
I wouldn’t use this. I’m deep integrating myself but for beginners, it will work.
Only needed if you are running 2.7.1
Hey you need to integrate the cookies using the plugin bbpress Integration for WordPress. Just google it and insert the code the plugin gives you into the wp-config.php and bb-config.php files.
Are you using buddypress? If your not I would recommend installing it and then using deep integration and the plugin buddybar for bbpress to achieve this functionality. You can find the plugin and help here: https://buddypress.org/forums/topic.php?id=3483
Login with the same username and password.
