USA Today reports that MySpace.com, the popular social-networking site, has stuck a partnership with the National Center for Missing & Exploited Children which will enable the site to send AMBER alerts online. AMBER is a program between law enforcement and the media which issues early warning in serious child abduction cases. This initiative is part of an upgrade of safety features aimed at addressing concerns of child-safety advocates, some of whom accuse the site of being too slow to keep its many teenage users safe from sexual predators…