Be sure to complete all subscriber and staff training before the cutover. Provide information that will allow them to be self-sufficient.
Publicising potential problems during training and defining steps to take will reduce calls to the Help Desk or Operations Center.
Encouraging subscribers to access Cisco Unity during the staging period will reduce the Day 1 load on the system.
Following up with your power users, subscribers with special requirements, admins, receptionists and Executive Row will again allow you to head off technical and policial problems.
Training staff while the system is being staged gets them up to speed on skills that will required while they man the Help Desk or Operations Center during the cutover.