Here are links to subscribing for each mailing list as well as a description for each:
JBoss Tools Announce (Big project news, release announcements):
https://lists.jboss.org/mailman/listinfo/jbosstools-announce
JBoss Tools Development (discussions for developers and contributors):
https://lists.jboss.org/mailman/listinfo/jbosstools-dev
JBoss Tools JIRA Issues (messages for new JIRA bugs/feature requests and updates):
https://lists.jboss.org/mailman/listinfo/jbosstools-issues
JBoss Tools Commits (messages for all commits into our CVS server):
https://lists.jboss.org/mailman/listinfo/jbosstools-commits
P.S. If you subscribed to the jbosside mailing lists your subscription have been moved to the jbosstools counter part.