Just to clarify, we will not have a private forum on TGB for NDA'd beta testers. The beta discussions and support will remain in the private beta newsgroup. This is not a Media Center only beta so we are working within the process of another team. Also, we want one location for communication.
I like to think of Microsoft Connect as the community for pre-released products while TGB can be thought of as a community for released products and/or publicly released information.
Hope this helps to clarify.
-Michelle_MS