If you log in to bbPress using your keymaster user, you should see a list of currently registered users on the dashboard. This list will include all currently registered WordPress MU users.
You may have noticed that the bbPress admin page somewhat resembles the admin page of WordPress MU. You should find most of the bbPress admin functions to be fairly intuitive.
While existing blog users will be copied over to bbPress without requiring any admin intervention, the same cannot be said for the reverse. If a user registers on the forums, they are given an entry in the WordPress MU user list, but the new user has no roles assigned to them. A similar situation arises with new blog users—they can create a blog, but they are unable to use the forums. This can cause problems and confusion for your users. Let's start by ensuring that our users only have to enter their login details once, to get logged in to the entire site.