Sign up for beta is closed for now. they put a limit on it >.<
read this below for more info
http://majornelson.com/2013/07/05/2013-xbox-live-update-for-xbox-360-public-beta-now-available/
read this below for more info
http://majornelson.com/2013/07/05/2013-xbox-live-update-for-xbox-360-public-beta-now-available/