I had the same problem and noticed that the NEXUS do not send the same syslog message as the other Cisco devices. So I went into Syslog viewer and copied the 'NCM Rule: Cisco IOS Realtime Change Notifcations' and called it 'NCM Rule: Cisco IOS Realtime Change Notifcations for Nexus'. Then I went and changed the Syslog Message Pattern in the Message tab to *Configured from vty*. Now my NEXUS do realtime changes as well.
NEXUS sends "Configured from vty" whereas all the other Cisco devices send "Configured from console"
