On F22 alpha according to /etc/systemd/journald.conf ForwardToSyslog defaults to "no". /var/log/messages is being filled with all messages going to journal. Manually setting ForwardToSyslog=no has no effect. Version-Release number of selected component (if applicable): systemd-219-9
This looks that it might have something to do with bz1147651.
*** This bug has been marked as a duplicate of bug 1147651 ***